Answer:
air
Explanation:
Explain in detail the science behind the most impactful scientific breakthrough of the last 300 years and how it impacts society today.
Note:
- Word length requirement is between 200 and 500 words
Every scientific discovery is fantastic, and some of them actually change people's lives.
What is Scientific Discovries?life science community to see which scientific discoveries you believe are the greatest in order to show science some extra love (as if we could love it any more).
Here is a list of the top ten scientific breakthroughs of all time, as noted on our blog over the past year, in no particular order, including CRISPR, genome editing, and penicillin.
It has given scientists the ability to physically remove genes and the regulatory components that control them, as well as, more exhilaratingly, to monitor their activity.
Therefore, Every scientific discovery is fantastic, and some of them actually change people's lives.
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two components of a cell NEED IN 5 MIN FOR BRINLIEST 0-0
Answer:
A cell has three main parts: the cell membrane, the nucleus, and the cytoplasm.
Explanation:
Hope it helps:)
Ageologist examines a rock sample that consists of flat layers. Under a microscope, the rocks appear to consist of grains of sand cemented together. What type of rock is this?
A. molten
B. igneous
C. sedimentary
D. metamorphic
Answer: The correct answer is C - Sedimentary.
Explanation: Sedimentary rocks are made up of layers of sediment, such as sand and other particles, that are cemented together. Igneous rocks form from molten material, while metamorphic rocks form from existing rocks that have been changed due to intense heat or pressure.
1. A woman claims to have been assaulted by three men. Evidence was collected from the victim. Statements were taken from each of the three suspects and the victim. DNA samples were also collected from each person. The suspects were arrested and charged with the crime. The case proceeded to trial. Which was the role of forensic scientists in this scenario?
A) charging the suspects and proceeding to trial
B) taking statements
C) arresting the suspects
D) collecting evidence from the victim and the suspects
2. The bullet from a suspect's pistol did not match the bullet found in a murder victim. There was blood on the carpet around the murder victim, but none on the suspect. The suspect's car was seen at the residence of the victim on the night of the murder. Carpet fibers from the room where the victim was found matched those found on the suspect. Based on Locard's principle, which is a correct conclusion and why?
A) The suspect was at the house because witnesses saw his car.
B) The suspect killed the victim with his gun.
C) The suspect killed the victim, which is known because carpet fibers on the suspect matched those in the room where the victim was found.
D) The suspect was in the room where the victim was found because of the matching carpet fibers.
3. A woman was found strangled in the basement of her home where she lived with her husband. The crime scene was processed and investigators left. The next day, the medical examiner reported that a scalloped, woven belt was used to strangle the victim. The police want to search the house again to look for such a belt. Which statement is true?
A) The police need to get a search warrant, according to Michigan v. Tyler.
B) The police do not need a warrant, according to the Third Amendment to the U.S. Constitution.
C) The police need to get a search warrant, according to Daubert v. Merrell Dow Pharmaceuticals.
D) The police do not need a warrant because the house is still a valid crime scene, according to Mincey v. Arizona.
4. A man was robbed in an alley outside a busy restaurant. He was assaulted with a baseball bat that was left at the scene. There were bloody footprints leading away from him. He was treated by paramedics and taken to a hospital. Two witnesses saw the robbery. The suspect fled the scene. Which task should be done by detectives?
A) take photographs of the scene including the bloody footprints
B) secure the crime scene
C) interview the witnesses
D) collect the bat and the blood samples
5. Which describes the activity of an arson investigator?
A) determining the angle of a bullet shot from an assassin
B) identifying the cause of death
C) reconstructing an explosion or fire
D) identifying the clothing found in a crime scene
6. What was the contribution of Calvin Goddard to forensic science?
A) He wrote the first book on questioned document examination to determine forgeries.
B) He invented the comparison microscope.
C) He refined the process of comparing bullets to make ballistic comparisons.
D) He was the first westerner to perform an autopsy.
7. A witness is scheduled to testify about a new unpublished procedure for detecting gases from dead bodies. The judge summarily rules that the witness cannot testify because the procedure has not been accepted by the scientific community. Which precedent is this ruling based on?
A) Frye standard
B) Miranda standard
C) Daubert ruling
D) Kumho standard
8. Which is NOT a duty of a first responder when arriving at a crime scene?
A) immediately take evidence photographs
B) locate witnesses
C) render aid and assistance
D) secure the crime scene
9. Who has most likely previously been a uniformed police officer?
A) detective
B) district attorney
C) coroner
D) forensic investigator
10. Who initially determines the time of death at a crime scene?
A) paramedic
B) police officer
C) coroner
D) detective
11. What is the first duty of the crime scene photographer?
A) take overall photos of the undisturbed crime scene
B) secure the crime scene
C) take photos of the witnesses
D) take close-up photos of the evidence
12. Which is necessary when setting up oblique lighting to reveal details of a tire track?
A) flash attached to a camera
B) external light source
C) ultraviolet light source
D) infrared light source
Answer:
1. D) collecting evidence from the victim and the suspects
2. D) The suspect was in the room where the victim was found because of the matching carpet fibers.
4. D) collect the bat and the blood samples
5. C) reconstructing an explosion or fire
6. C) He refined the process of comparing bullets to make ballistic comparisons.
7. A) Frye standard
8. B) locate witnesses
9. D) forensic investigator
10. A) paramedic
11. A) take overall photos of the undisturbed crime scene
12. C) ultraviolet light source
if a solute concentration gradient has been established across a membrane, the permeable solute will diffuse across the membrane:
Permeable solute will diffuse across a membrane if a solute concentration gradient has been established: from the side with a higher concentration to the side with a lower concentration.
The bigger the concentration difference between two locations, the steeper the concentration gradient and the faster the rate of diffusion.
Temperature: As the temperature rises, so does the energy and hence the movement of the molecules, which increases the rate of diffusion.
The concentration gradient, membrane permeability, temperature, and pressure all influence the rate of diffusion.
The concentration gradient influences the movement of osmosis; the lower the concentration of a solute inside a solvent, the faster osmosis will occur in that solvent.
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What happens to intensity when you increase the area over which a given amount of light energy is distributed?
Answer:
Light intensity decreases with distance from source to receiving surface (sink), and the rate of decrease is in proportion to the square of the distance between emitter and receiver.
In tomatoes, tall vines (T) are dominant to dwarf vines (t), and red fruit (R) is dominant to yellow fruit (r).
A farmer mates a homozygous tall, red tomato plant (TTRR) with a heterozygous tall, red tomato plant (TtRr).
What is the percent chance that the offspring will be dwarf plants with yellow fruit?
In this observation, the percent chance that the offspring will be dwarf plants with yellow fruit is 0%.
What is a dihybrid cross?In the question cross between a homozygous tall, red tomato plant (TTRR) with a heterozygous tall, red tomato plant (TtRr).
Cross between: TTRR X TtRr
Gametes: (TTRR) - TR
(TtRr) - TR, Tr, tR, and tr
Phenotype: TTRR TTRr TtRR TtRr
The percent chance that the offspring will be dwarf plants with yellow fruit is 0%.
The cross is attached in the image below.
Therefore, dwarf plants with yellow fruit would be - ttrr that is not produced in this cross, so dwarf plants with yellow fruit is 0%.
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When diffusion has reached equilibrium, we say that the net movement of the molecules is zero. Does this mean these molecules below would stop moving? Explain using the image below.
When diffusion has reached equilibrium, we say that the net movement of the molecules is zero, which effectively means these molecules would stop moving due they only move in presence of a concentration gradient, which is a process that does not require any input of energy.
What is the cell process of diffusion through a biological membrane?The cell process of diffusion through a biological membrane refers to the net movement of particles through a selective barrier called a plasma membrane which allows the passage of molecules from a region of higher concentration to a region of lower solute concentration.
Therefore, with this data, we can see that the cell process of diffusion through a biological membrane is based on the net movement of small molecules across the plasma membrane in a process that does not require energy to produce this transport.
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. The atomic number (Z) of an element is the number of protons in the nucleus of atoms of that element. Because the net charge on an atom is zero, the number of protons is equal to the number of electrons. Thus, the atomic number also gives the number of electrons in a neutral atom. The mass number (A) of an atom is the total number of nucleons (protons plus neutrons). Therefore, the number of neutrons in an atom can be found by subtraction:
The atomic number (Z) of an element is the number of protons in the nucleus of atoms of that element.
What is atomic number?Atomic number is an important property of all chemical elements. It is the number of protons in the nucleus of an atom and is unique for each element. Protons have a positive charge and are the smallest particles that make up an atom.
This number is unique to a given element and is used to identify it. Since the net charge on an atom is zero, the number of protons is equal to the number of electrons. Therefore, the atomic number also gives the number of electrons in a neutral atom.
The mass number (A) of an atom is the total number of nucleons (protons plus neutrons). It is also sometimes referred to as the atomic mass number. The number of neutrons in an atom can be found by subtracting the atomic number from the mass number:
Number of neutrons = Mass number (A) - Atomic number (Z)
For example, the mass number of carbon-12 is 12, and its atomic number is 6. Therefore, the number of neutrons in carbon-12 is 6 (12 - 6 = 6).
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Write the three factors that affect surface
ocean currents.
1. Wind direction.
2. Coriolis forces from the Earth's rotation.
3. Position of landforms that interact with the currents.
Hope this helps you!!
A student made an energy pyramid that has 3 levels. The bottom level had 100 rectangles, how many rectangles must be in the top energy level?
If the bottom level of the energy pyramid had 100 rectangles, the top energy level would have only 1 triangle.
Energy pyramidThe energy pyramid is a pyramid that shows how energy is transferred from one trophic level to another in an ecosystem. According to findings, only about 10% of the energy from the lower pyramid level gets to the higher energy level.
The lowest energy level in a typical energy pyramid is occupied by producers. Thus, assuming that a total of 100 J of energy is available at the producer level, only 10 J (1o% of 100) will get to the next level which would be the primary consumer.
In other words, if the bottom level of the energy pyramid designed by the student had 100 rectangles, the next level would have 10 rectangles.
Thus, the topmost level of the student's energy pyramid would have:
10% of 10 = 10/100 x 10 = 1 reactangle.
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What is a Disadvantage to limiting livestocks movement
The ecology suffers greatly from livestock farming. It is the main cause of biodiversity loss, habitat damage, and water pollution, contributing to half of the world's greenhouse gas emissions.
What drawbacks do extensive livestock operations have?Chemical fertilizers, herbicides, and insecticides of various kinds are used in intensive farming. Animals are housed in holding facilities, which can result in overpopulation, pollution, and the spread of diseases and infections.
What is the primary issue we have with our livestock?Both land and carbon are used up while raising animals for food. Farm animals such as cows, chickens, and pigs emit enormous volumes of methane gas and need pastures, both of which are at risk as a result of desertification and soil erosion as global temperatures rise.
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LIMITED TIME, HELP PLEASE!!!!!!!
Peppered moths can have either a light wing color or a dark wing color. A scientist studied populations of both light and dark peppered moths over a 10-year period. A graph of the data he collected is shown in the image.
Based on the graph, which is the best conclusion to make about
changes in the moth populations by the end of the study period?
Select one:
At present, dark-winged peppered moths are being naturally
selected for survival.
A new food source has become available only to the light-winged
peppered moth.
A disease has affected only the dark-winged peppered moth.
At present, wing color is not a factor in the success of peppered
moths.
The effects of exercise with varying intensity on the immune system.
Answer:
Excessive amounts of prolonged high-intensity exercise may cause a down-regulation of immune function
Hope this helps :)
Which of the following is an accurate statement regarding human evolution?
Select all that apply.
The first humans evolved in Africa.
In the latest phase of human evolution, there has been a greater reliance on culture.
The fossil record contains creatures with features that are intermediate between those of modern humans
and quadrúpedal apes.
Once bipedality, tool use, and larger brains evolved in humans, humans stopped evolving
The following is an accurate statement regarding human evolution :
The first humans evolved in Africa.The fossil record contains creatures with features that are intermediate between those of modern humans and quadrupedal apes.In the latest phase of human evolution, there has been a greater reliance on culture.Human evolution is the evolutionary process in primate history in which Homo sapiens emerged as a distinct species of the Hominidae that includes the great apes.
Human evolution, the process by which humans evolved on Earth from now-extinct primates. Zoologically, we humans are Homo sapiens, a culture-retaining, upright, ground-dwelling species that most likely first evolved in Africa about 315,000 years ago.
Human evolution is a long-term process of change in which humans descended from an ape-like ancestor. Scientific evidence suggests that the physical and behavioral traits common to all humans descended from an ape-like ancestor and evolved over a period of approximately 6 million years.
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Refer to the figure above. What is the function of the ACC sequence at the 3' end?
A. It attaches to an amino acid.
B. It base pairs with the codon of mRNA.
C. It is the active site of this ribozyme.
D. It stabilizes the tRNA-amino acid complex.
Function of the ACC sequence at the 3' end is it attaches to an amino acid.
'What is ACC sequence at 3' end?'
All mature tRNA molecules have a conserved ACC sequence at their 3' end, which serves as the location where amino acids are attached. The ubiquitous ACC enzyme, a unique RNA polymerase that does not need a nucleic acid template for nucleotide addition, acquires and maintains its sequence through stepwise nucleotide addition. The mechanism of template-independent nucleotide selection differs across the two physically diverse groups of ACC enzymes that have been identified through crystal structural study.
Importantly, the kinetic experiment shows that the E. coli ACC enzyme has an innate ability to distinguish against tRNA backbone breakage at each step of ACC production.
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Which of the following is NOT a checkpoint that controls the progression of the cell cycle? O Cyclins and cyclin-dependent kinases are proteins that are responsible for advancing a cell through the phases of the cell cycle_ O The G2 checkpoint checks for DNA damage and determines if all of the DNA is replicated: O The metaphase checkpoint determines if all chromosomes are attached to the spindle apparatus O Cytokinesis involves the formation of cleavaze furrow to separate the cells are favorable for cell division and if the DNA is O The restriction point determines if conditions undamaged
The restriction point is not a checkpoint that regulates the cell cycle's advancement.
The series of activities that take place in a cell that prepare it for division and duplication is known as the cell cycle (replication). Interphase (G1, S, and G2) and the mitotic phase are the two primary stages that these events can be separated into (M).
Numerous checkpoints that make sure the cell is prepared to advance to the following phase regulate the advancement through the cell cycle. Proteins called cyclins and cyclin-dependent kinases are in charge of moving a cell through the many stages of the cell cycle.
The G2 checkpoint assesses if all of the DNA has been copied and looks for DNA damage. A chromosome's attachment to the nuclear envelope is determined at the metaphase checkpoint.
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1. Easily visible anatomical traits are only one kind of evidence scientists rely on when classifying organisms. Additional evidence comes from many different sources, including the fossil record and genomic analysis. Explain how these additional sources of evidence together are used to build a cladogram.
Additional sources of evidence together with genomics data are used to build a cladogram because there is info based on morphological, and embryological data that indicates homology.
What is homology in evolution?Homology in evolution refers to the similarities between organisms that are due to common ancestry, i.e. the presence of shared characteristics between species that are attributed to the inheritance of similar structures from a common ancestor such as the front limbs of a human and a horse.
Therefore, with this data, we can see that supplementary sources of information in combination with genomic information are employed to construct a cladogram.
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which of the following refers to the transformation of stimulus energy into neural impulses? responses perception perception bottom-up processing bottom-up processing top-down processing top-down processing transduction transduction psychophysics
Transduction refers to the transformation of stimulus energy into neural impulses.
A virus or other viral vector introduces foreign DNA into a cell through a process known as transduction. One illustration of horizontal gene transfer is the viral transmission of DNA from one bacterium to another.
In contrast to conjugation, which involves physical contact between the cells giving and receiving DNA, transduction is DNase resistant (transformation is susceptible to DNase).
Molecular biologists frequently utilize transduction to successfully transfer a foreign gene into the genome of a host cell (both bacterial and mammalian cells).
At the University of Wisconsin-Madison, researchers Norton Zinder and Joshua Lederberg identified transduction in Salmonella in 1952.
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The conversion of stimulus energy into neuronal impulses is referred to as transduction.
Transduction occurs when a virus or other viral vector delivers foreign DNA into a cell. The viral transmission of DNA from one bacteria to another is an example of horizontal gene transfer.
Transduction, unlike conjugation, which requires physical contact between the cells providing and receiving DNA, is DNase resistant (transformation is susceptible to DNase).
Transduction is a technique used often by molecular biologists to effectively transfer a foreign gene into the genome of a human host (both bacterial and mammalian cells).
In 1952, researchers Norton Zinder and Joshua Lederberg at the University of Wisconsin-Madison discovered transduction in Salmonella.
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fill in the blank.while research is still being conducted to identify beneficial species of bacteria, two species,___and___, are known to be beneficial. lactobacillus sp.; escherichia sp. bifidobacterium sp.; staphylococcus sp. lactobacillus sp.; bifidobacterium sp. bifidobacterium sp.; enterococcus sp.
while research is still being conducted to identify beneficial species of bacteria, two species, Lactobacillus and Bifidobacterium are known to be beneficial.
SO , the correct option is C ;
Acidophilus can be used as a probiotic to help your body's healthy bacteria develop. Acidophilus may also aid in the treatment of a number of medical disorders such as digestive problems, yeast infections, and eczema.
Now that you understand how probiotics operate, let's look at three popular strains: Lactobacillus plantarum, Lactobacillus brevis, and Leuconostoc mesenteroides.
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describe the tympanic membrane and temporal artery thermometers, and compare their use with othe forms of termperature meaureent
The tympanic membrane and temporal artery thermometers are quick and easy to use. Oral and rectal thermometers are both dangerous.
The temperature on the forehead (temporal) scanner is typically 0.5°F (0.3°C) to 1°F (0.6°C) lower than the oral temperature.
The temporal artery temperature is one degree Fahrenheit higher than the oral body temperature, roughly the same as the rectal temperature, and two degrees Fahrenheit higher than the axillary body temperature.
Remote forehead thermometers monitor the temperature of the temporal artery in the forehead using an infrared scanner.
The temporal artery in the forehead is measured with a temporal thermometer, while the eardrum is measured by a tympanic thermometer.
Tympanic temperature was 0.7°C higher than temporal temperature in patients without symptoms and 0.8°C higher in patients with chills in the 39.0°C or higher subgroup.
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A. protective membranes
C. storage units
0
Vacuoles are the
B. brain
for the cell.
D. unnecessary organelles
Answer:
it's d ️️
Explanation:
I did it
 What data did the test on the purified substance produce how did the data further support the hypothesis that DNA is the transforming factor
Based on research analysis, the data the tests on the purified substance produce is a negative result in chemical tests to observe proteins, but a strongly positive result in a chemical test to observe DNA.
What are the functions of DNA?Deoxyribonucleic acid is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning.
DNA is the information molecule. It stores instructions for making other large molecules, called proteins. These instructions are stored inside each of your cells, distributed among 46 long structures called chromosomes.
DNA is made of nucleotides. A nucleotide has two components: a backbone, made from the sugar deoxyribose and phosphate groups, and nitrogenous bases, known as cytosine, thymine, adenine, and guanine.
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what do the receptor cells for hearing static equilibrium and dynamic equilibrium have in common
The receptor cells for hearing, static equilibrium, and dynamic equilibrium all have hair cells that are responsible for sensing the stimulus and sending signals to the brain.
In the ear, these hair cells are located in the cochlea and are responsible for converting sound waves into neural impulses. In the inner ear, the hair cells responsible for static equilibrium are located in the utricle and saccule, while the hair cells responsible for dynamic equilibrium are located in the semicircular canals. These hair cells all have similar structures, including hair-like protrusions called stereocilia, which are responsible for detecting the stimulus and initiating the neural response.
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An example of an organism that has only behavioral controls over its body temperature is the. A) house sparrow. B) penguin. C) bluefin tuna. D) gray wolf.
The green frog is an example of an organism that regulates its body temperature solely through activity.
What kind of organism can keep its internal temperature at a level that is adequate for life?Endotherms use heat produced internally to keep their body temperatures stable. No matter the surroundings, their body temperature tends to remain constant. Ectotherms rely mostly on outside heat sources, and the environment's temperature affects how hot or cold they are inside.
What physiological state is characterized by decreased activity and metabolism?Torpor, also known as dormancy, is a physiological and behavioral state that is widely recognized in both plants and animals and typically denotes inactivity and a slowed metabolic rate. It can involve a number of physiological responses to various environmental cues, such as temperature, water, or food.
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what is metaphase stage
Answer:
a stage during the process of cell division (mitosis or meiosis).
Answer: Metaphase is the third phase of mitosis, the process that separates duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells. During metaphase, the cell's chromosomes align themselves in the middle of the cell through a type of cellular "tug of war." The chromosomes, which have been replicated and remain joined at a central point called the centromere, are called sister chromatids.
Explanation: HOPE THIS WAS HELPFUL
what is telophase stage
Answer: Telophase is the final stage in cell division. During telophase, the nuclear envelopes reform around the new nuclei in each half of the dividing cell. The nucleolus, or ribosome producing portions of the nucleus return. As the cell has finished moving the chromosomes, the main parts of the spindle apparatus fall depolymerize, or fall apart.
Explanation: Hope this was helpful
HELP!!!!!!!!!!!!LIMITED TIME!!!!!!!!!!!!!!!
Given the following phylogenetic tree, which group of invertebrates
evolved the earliest in the Earth's history?
Select one:
Arthropods
Flatworms
Sponges
Cnidarians
What would be a typical phenotypic monohybrid ratio in which a lethal allele is involved?
O 13:5
O 2:1
O 9:3:3:1
O 3:1 (it is not this one)
O 6:2:3:1
2:1. Alleles that result in the death of the carrying organism are known as lethal alleles sometimes spelled lethal or lethals.
They frequently arise from mutations in genes required for growth or development. Depending on the gene or genes involved, lethal alleles may be dominant, recessive, or conditional. A monohybrid cross occurs when two organisms with distinct variants at the same genetic locus are bred. Two or more variations for a single gene's position control the character(s) under study in a monohybrid cross.
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Which of the following is NOT a difference between anaphase I and anaphase II?
A. At the end of anaphase I, each chromosome is composed of two chromatids and at the end of anaphase II, sister chromatids have separated, becoming daughter chromosomes
B. Anaphase I occurs in a haploid cell while anaphase II occurs in a diploid cell.
C. Sister chromatids separate during anaphase II while homologous chromosomes separate during anaphase I.
D. The cell undergoing anaphase II is genetically different from what it contained while undergoing anaphase I.
Anaphase I occurs in a haploid cell while anaphase II occurs in a diploid cell.
The correct option is B.
A chromosome is a lengthy DNA molecule that stores all or a portion of an organism's genetic information. Together with chaperone proteins, histones adhere to and compress the DNA molecule to shield it from damage. Histone proteins make up the majority of eukaryotic chromosomes. Controlling transcription depends on the unusual three-dimensional structure of these chromosomes. In eukaryotic cells, the nuclear envelope is a carefully regulated membrane barrier that segregates the cytoplasm from the nucleus (NE). It is made up of many proteins that have been connected to chromatin organisation and gene regulation.
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