The method used when an entire mole is removed for examination under a microscope is called an excisional biopsy.
This method involves the surgical removal of the entire mole and some surrounding skin which is then examined under a microscope to check for any abnormal cells or signs of cancer. This method is typically used when a mole is suspected to be malignant or when it cannot be clearly diagnosed as benign through other methods such as a shave or punch biopsy.
The key benefit is that, as opposed to an incisional biopsy, when a bit of the tissue is taken to provide a diagnosis but it will likely still need to be treated later, the aberrant tissue may be identified, diagnosed, and removed in one operation.
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You are handed a pring that i 0. 400 m long. You hang the pring from a hook
on the ceiling and attach a 0. 750-kg ma to the other end of the pring. The
tretched pring length i 0. 450 m. What i the pring contant?
The spring constant with given length that stretches upto certain length and has specified mass has a spring constant that is calculated to be 147 N/m.
Given that,
Initial length of the spring = 0.400 m
Final length of the spring = 0.450 m
Change in length, Δx = 0.450 m - 0.400 m = 0.050 m
Mass of the hung object = 0.750 kg
Weight of the hung object, w = 0.750 × 9.8 N = 7.35 N
From Hooke's law it is said that, mathematically
Spring constant = Weight of the hung object/ change in length
Putting in the above given values into the equation, we have,
Spring constant = 7.35/0.050 = 147 N/m
The required spring constant is calculated to be 147 N/m.
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Together, the car and trailer have a mass of 2000 kg. At what rate will the car and trailer accelerate?
The weight of the automobile and trailer together is 2000 kg. The vehicle will accelerate at a rate of 2.5 m/s2.
What does average acceleration formula entail?Acceleration is measured in meters per second squared (ms2), or m s 2. Formula for Average Acceleration: The final velocity minus the initial velocity, divided by the change in time, is the equation for average acceleration (a). A = v t = v f v I t.
What is the linear momentum formula?The product of an object's mass (m) and velocity (v) is its linear momentum. Higher momentum makes it more difficult to halt an object. P = mv is the equation for linear momentum.
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How to solve this electrical circuit?
The resistor that is equivalent to the resistance of the circuit is 1 2/7 Ohms
What is an equivalent resistance of a circuit?The equivalent resistance of a circuit is the (single) resistance that can replace the combination of resistances in the circuit such that the current flowing in the circuit remains the same.
Please find attached the drawing of the circuit, created with an online circuit building tool.
Whereby the capacitor also acts as a resistor of 6 Ohms, we get;
Resistors R₄, R₅, and R₆ are parallel
The resistor equivalent to the three resistors is found as follows;
Req₁ = 1/(1/R₄ + 1/R₅ + 1/R₆)
Therefore, Req₁ = (1/(1/2 + 1/1 + 1/6)) = 0.6
Req₁ is in series with R₁, therefore;
Req₂ = Req₁ + R₁ = 0.6 + 3 = 3.6
Req₂, (Req₁ + R₁ combined) is parallel to R₂ and R₃, therefore;
Req₃ = 1/(1/Req₂ + 1/R₂ + 1/R₃)
Req₃ = 1/(1/3.6 + 1/3 + 1/6) = 9/7 = 1 2/7
The equivalent resistor of the circuit is 1 2/7 ohms
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What is the intensity of 60 dB sound?
The intensity of 60 dB sound is 10⁻⁶ W/m².
A common conversation between two persons seated at a distance of around one meter (3 14 feet) is as loud as 60 dB. It is equivalent to the typical noise level in a restaurant or office.
The decibel scale is a logarithmic one rather than a linear one. Accordingly, 10 dB denotes a sound that is 10 times louder than 0 dB, which represents no sound at all. Now, a sound at 20 decibels is 100 times louder than one at 0 decibels. And so on until a sound that is 100 decibels is 1 billion times louder than total silence (0 decibels).
A sound at 60 dB is therefore 100 times louder than a sound at 40 decibels and 1000 times louder than a sound at 30 decibels, while being 10 times louder than a sound at 50 decibels.
The formula for sound volume is L = log(I/I₀), or (I/I₀) = 10^L.
Given that L = 60dB = 6bel and that we know that I₀ = 10⁻¹² W/m²,
I/I₀ = 10⁶.
or I = 10⁻¹² × 10⁶ = 10⁻⁶ W/m²
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A block of mass mm is initially at rest on a rough horizontal surface when a constant force FF is exerted on it, as shown. The block accelerates to the right and is moving with speed vv once it has moved a distance dd. Which of the following equations can be used to solve for the force of friction exerted on the block by the surface?
F m v2 А F-f= 2d B F-f=ma с F-f= mv2 2d D f-F = mv2 d E f-F = mv2 2d
Block B on the exterior f-F = ma c f-F = mv2 2d f-F = D = mv2 d f-F E f-F = v2 2d.
What is meant by mass surface?A thing's top, exterior, or outermost layer: Tropical rain forests once covered 10% of the earth's surface. The marble has a smooth, polished surface.
The surface of the picture is covered in little fissures. The bowl's exterior has a glossy finish. The wood was rough on the outside. Ice-covered roads ought to be avoided. The phrase "on the surface" describes how something seems, even if it isn't really the case.
The formulas F- f = mv2 / d can be used to determine the force of friction that the surface exerts on the block.
Briefing:
F - f = ma
a = v/t
t = d/v
F - f = m × v / t
F- f = m ×
F- f = m × v²/d
Therefore,
F- f = mv² / d
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is/are defined in the NEC as the conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served
The cables and machinery used to transport electric energy from the supplying utility to the wiring system of the premises served are referred to as "service" in the NEC. The Service Point is the location where the customer's premises wiring starts and the utility supply terminates.
is the distance between the utility's serving point and the service point specified as the overhead conductors?Drop in service. between the service point and the utility's electrical supply infrastructure, the overhead conductors.
The conductors from the service point to the service disconnecting means are what are referred to as by the NEC.Service conductors are the wires that run from the service point to the method of terminating the service (service equipment, not meter). For both above (service drop) and subterranean, service conductors would include service-entrance conductors (service lateral).
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What is better static or dynamic stretching?
Explanation:
This intense stretching method uses bouncing movements to push your body beyond its normal range of motion. Whereas static stretches are performed slowly and gradually, the ballistic method stretches muscles much farther and faster. You can do many of the same stretches as ballistic or static stretches.
How much heat is given off when 210.0 g of water at 0°C freezes into ice?
Answer:
it gives off 71.0 kJ of heat.
Explanation:
A certain light truck can go around a flat curve having a radius of 150 m with a maximum speed of 34.5 m/s. With what maximum speed can it go around a curve having a radius of 60.0 m
With 20.23 ms⁻¹, maximum speed can it go around a curve having a radius of 60.0 m
What's the maximum speed?The highest rate of speed a person can reach is called maximum speed. When athletes alter the magnitude (how quickly they are moving) or direction (or both) of their motion, or both, their acceleration changes as well since acceleration is related to velocity, which has both a magnitude and a direction connected with it.
ac max = V² max / R ....(1)
Inserting given values we get
ac, max = (34.5)² / 150 = 7.935 ms⁻²
For a changed radius of the curve of 60.0 m, the maximum safe speed from (1) becomes
Unew, max= √ac, max R new
Unew, max = √6.826 x 60
Unew, max 1 = 20.23 ms⁻¹, rounded to one decimal place.
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What is the formula of law of lever?
"Effort multiplied by an arm equals burden multiplied by an arm," The various loads on the proportionally shorter load arm can be moved by the effort arm.
What does a class lever mean?A lever is a straightforward device with a solid beam and a fulcrum. The effort (input force) and load (output force) are applied to the beam's ends. The pivot of the beam is thought to be the fulcrum.
What do you name a lever?Levers are devices that increase force, to put it simply. Because they merely have the handle and the fulcrum, we refer to them as "basic machines." The "arm" of the lever is the handle or bar; it is the portion that you push against or pull towards.
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A naval navigator is using sonar to look for sunken cargo. The waves he is using have a frequency of 120
kHz and a wavelength of 3 mm. How far away is the cargo if the sound wave is emitted at exactly 9:24 a.m.
and returns to hit the ship's sensor 3 seconds later?
Answer should be in meters
With the use of wave speed and echo formula, the distance is 540 m
What is Echo ?Echo can simply be defined as a reflection of sound wave. Where as, Sound wave is longitudinal wave.
Given that a naval navigator is using sonar to look for sunken cargo. The waves he is using have a frequency of 120 kHz and a wavelength of 3 mm.
The wave speed V = Fλ
Where
V = ?F = 120 KHz = 120,000λ = 3 mm = 0.003 mV = 120000 × 0.003
V = 360 m/s
How far away is the cargo if the sound wave is emitted at exactly 9:24 a.m. and returns to hit the ship's sensor 3 seconds later?
Speed V = 2S/t
where
S = distance ?t = time taken = 3 s360 = (2 × S)/3
360 × 3 = 2S
S = 1080/2
S = 540 m
Therefore, the cargo is 540 m away
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A 2.0 kg book is lying on a 0.75-m-high table. You pick it up and place it on a bookshelf 2.3 m above the floor. During this process, your hand does _______ work on the book.
The weight of the book and your lifting power will be the only two forces operating, assuming that air resistance is minimal (gravity).
The book's displacement was x=(2.3-0.75)m=+1.55m.
The book weighs W= m(-g)= 2.0 kg(-10N/kg)= 20 N.
Therefore, the weight's work (energy delivered by the weight) is equal to W.x (-20N).
(+1.55m) = -31 Nm =-31 J.
This outcome, -31J, demonstrates that the weight caused the rising book to lose 31J of kinetic energy, increasing the gravitational potential energy of the book.
You lifted the book, which gave it kinetic energy from the chemical energy stored in your muscles. The weight is thereby decreasing the kinetic energy of the book while the lifting force from you increases it.
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Gravity on the surface of the moon is only 1 6 as strong as gravity on the Earth. What is the weight of a 35 kg object on the Earth
Answer:
Weight of a 35kg object on Earth is 350N, while it is 56N on the Moon.
Explanation:
The conversion of mass (kg) to weight (N) on Earth is 1kg to 10N.
Thus, the weight of a 35kg mass on Earth is
35kg × 10 = 350N
On the Moon, conversion of mass to weight is 1kg to 1.6N.
Thus, the weight of a 35kg mass on the Moon is
35kg × 1.6 = 56N
Remember, mass remains constant regardless of location, while weight depends on the strength of the gravitational field.
Echolocation only works well when the object is as long as or longer than one wavelength of the sound produced.
a) Estimate the size of the smallest object a bat can detect using echolocation when the air temperature is 22 °C
The size of smallest object that a detect wing is 22°C bat can echolocation when air temperature is 31 mm.
Bat need to use because as high frequencies for echolocation compared to lower frequencies, higher. frequencies gives them more regarding size of the object in speed and frequency the prey direction of its waver are not early detailed information their path, range, pray. Also high detected by the prey.
For care the Jame of bat, dolphin frequency as explained in alio high radiation. Thus despite poor visibility under water, dolphin can high frequency and avoid to catch its wave it Predator. we there to find its path and to catch its prey and also to avoid its peredetor.
Bat sounds are emitted only during wing upbeat to minimize physiological costs. Air pressure in calls is just below blood pressure in lungs physiological maximum. FM is best for determining target distance Measure time delay between pulse and echo return FM sweep labels each part of pulse with a frequency value.
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which of the two stationary charges q1=2 c and q2=10 c will create stronger magnetic field?
Because the charges at rest are unable to produce a magnetic field, neither of the two stationary charges will do so.
There is no magnetic field created when a charge is stationary since there is no motion inside the charge. Thus, nothing except an electric field is created.
Charges that are at rest can also feel the electric force. Charges in motion can experience magnetic force. Therefore, the electric field must not be zero and the magnetic field may or may not be zero if a charged particle at rest experiences an electromagnetic force.
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given the masses of p1, p2, p3, and p4 are respectively 1kg, 2kg, 3kg, and 4kg, determine the value of the greatest horizontal range of the four projectiles, assuming they land at the same height that they fire at.
As Projectile range is independent of mass, so They all will have same range.
When an object is close to Earth's surface, its gravitational attraction is calculated using the formula F = mg, where m is the object's mass and g is a constant whose value varies depending on the location. On the surface of the earth, it averages 9.81 meters per second. And when one moves away from the surface in either an inner or an outward direction, this value drops.
Although the strength of the earth's gravitational pull changes depending on the mass of the object, the acceleration caused by it is constant (of course close to the surface). Consequently, when two items of different masses are dropped from the same height, they hit the ground simultaneously (neglect air resistance).
Any motion of a projectile simply consists of vertical and horizontal motion. Regardless of the direction the projectile is going in, gravity controls vertical motion since it only acts in that direction. Additionally, the acceleration caused by gravity is not reliant on the mass of the item. Therefore, the mass has no bearing on the vertical motion.
A projectile moves horizontally in a very straightforward manner. A projectile is not affected by horizontal forces. As a result, its horizontal velocity does not change. Additionally, the range is influenced by horizontal velocity and flying time. Flight time is influenced by vertical motion.
We now know that mass has no bearing on flying duration or range. And if you run into a projectile motion problem, simply divide the problem into horizontal and vertical motions. And handle it the same way you would a single-direction motion. greatly simplifies matters.
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Why is i0 10 12 W m2 used as a reference intensity for intensity level?
Since I0 is the lowest sound intensity that a person with normal hearing can detect, it is chosen as the reference point. Given that log10 1 = 0, the decibel level of a sound with an intensity of 10–12 W/m2 is = 0 dB. In other words, the human hearing threshold is zero decibels.
The reference value I0 is 10–12 W/m2, which corresponds to the threshold of hearing intensity at 1000 Hz. The Sound Intensity Level, or SIL for short, is the intensity decibel scale. The related sign, like in our text, is LI.
Much more frequently than sound intensities in watts per square meter, sound intensity levels are expressed in decibels (dB). Both the scientific literature and the public media use decibels as their preferred measurement unit. The rationale behind this decision of units has to do with how we hear. There is a reference intensity, I0 = 1012 W/m2. The lowest or threshold intensity of sound that a person with normal hearing can perceive at a frequency of 1000 Hz is specifically known as I0. The degree of sound intensity is not the same as the intensity. is a unitless quantity that informs you of the sound level in relation to a predefined standard (1012 W/m2, in this case), as it is defined in terms of a ratio.
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Of the following objects, on which one would time on its surface run most slowly?
a. An object with the same mass as the Sun but twice as large in radius
b. The Sun
c. An object with the same mass as the Sun but only half as large in radius
The time on the surface of an object would run most slowly on an object with the same mass as the Sun but twice as large in radius.
What is mass?
Mass is a measure of the amount of matter in an object and is typically expressed in kilograms (kg). It is an intrinsic property of matter and is different from weight, which is a measure of the force of gravity acting on an object. Mass is an important factor in determining the physical properties of an object, such as density, momentum, and inertia. Mass is also used to calculate the gravitational force between two objects, as well as the energy required to move it.
This is because the surface gravity of an object is inversely proportional to the square of its radius. Therefore, the object with the same mass as the Sun but twice as large in radius would have a much lower surface gravity, and time would run more slowly on its surface.
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A standing wave is set up in a pipe with both ends open. The frequency of its first harmonic is 300 Hz. What is the length of the pipe? Take the speed of sound to be 340 m s–1. Give your answer in meters
When the frequency of a standing wave set up in a pipe (with both ends open) first harmonic is 300 Hz, the length of pipe is 0.567 metres.
Therefore the answer is 0.567 m.
The speed of sound in air is approximately 340 m/s, and the wavelength of the first harmonic of a standing wave in an open pipe is twice the length of the pipe. Therefore, if the frequency of the first harmonic is 300 Hz, the wavelength can be calculated as:
wavelength = speed of sound / frequency
wavelength = (340 m/s) / (300 Hz)
The length of the pipe can be calculated as half the wavelength:
L = wavelength/2
L = (340 m/s) / (2×300 Hz)
L ≈ 0.567 m
So the length of the pipe is 0.68 m
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calculate the average speed of the cyclist travelling 100 meters in 40 seconds
To find the average speed of the cyclist, we need to divide the distance traveled by the time it took to travel that distance. So we would divide 100 meters by 40 seconds, which gives us 2.5 meters per second. This is the average speed of the cyclist.
Answer:
The Average Speed is 2.5metres per second
Explanation:
Using Distance,Time,Speed Triangle,
[tex]S = \frac{D}{T}[/tex]
[tex]S = \frac{100}{40}\\[/tex]
[tex]S = 2.5[/tex]
Hence , the average speed is 2.5m/s
Describe what you could do to make the magnetic disk rotate faster
You could do to make the magnetic disk rotate faster: regular usage of a disc defragmentation program.
What is magnetic disk?A magnetic disk is a storage device that writes, rewrites, and accesses data using the magnetization process. It has a magnetic layer that retains data as tracks, spots, and sectors.
You could do to make the magnetic disk rotate faster:
Plan regular usage of a disc defragmentation program.Try to keep at least 20% of your disc space free, if you can. Defragmentation is facilitated and fragmentation is reduced as a result. Utilize a program like Crystal DiskInfo to regularly check the condition of your drive.Learn more about magnetic disk here:
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do you think humans might be useful as index fossils in the future. Explain.
Index fossils are fossils that are used to help determine the relative age of rock layers and sedimentary strata. They are typically small, widely distributed organisms that lived for a relatively short period of time and are characteristic of a specific geological period. Index fossils are useful because they can help geologists and paleontologists to determine the relative age of rock formations and to understand the Earth's geological history.
It is unlikely that humans would be useful as index fossils in the future, as the time period during which humans have existed on Earth is relatively short compared to the age of the Earth as a whole. In addition, humans are not small, widely distributed organisms like many of the commonly used index fossils. Instead, humans are large, highly adapted organisms that have a wide range of habitats and are found on most of the continents.
However, it is possible that artifacts or other remains associated with human activity could be used as index fossils in the future. For example, the presence of certain types of tools or other materials might be used to help determine the relative age of a site or to understand the environmental conditions and human activity in a particular region at a specific point in time.
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a box of chocolate bars weighs 180N. Its base has an area of 0.09m2. what pressure does it exert on the ground
Answer:
2000
Explanation:
180/0.09
=2000
pressure=force/area
A theme park is planning out a new free-fall ride. The drop is almost perfectly frictionless, with a distance of 190 meters. Assuming that the initial velocity was zero, what would be the speed at the bottom of the drop?
a-53 m/s
b-61 m/s
c-67 m/s
d-72 m/s
Answer:
Approximately [tex](-61)\; {\rm m\cdot s^{-2}}[/tex], assuming that [tex]g = 9.81\; {\rm m\cdot s^{-2}}[/tex].
Explanation:
Under the assumptions, the vehicle would be in a free fall. Acceleration would be constant: [tex]a = (-g) = (-9.81)\; {\rm m\cdot s^{-2}}[/tex].
Let [tex]u[/tex] denote the initial velocity of the vehicle. Let [tex]v[/tex] denote the velocity of the vehicle at the bottom of the drop. Let [tex]x[/tex] denote the displacement of the vehicle during the drop.
It is given that the initial velocity is [tex]u = 0\; {\rm m\cdot s^{-1}}[/tex]. During the drop, displacement would be [tex]x = (-190)\; {\rm m}[/tex] (negative since the vehicle is below where it started.) The value of final velocity [tex]v[/tex] needs to be found.
It is known that the vehicle is moving downwards at the end of the fall. Therefore, the value of [tex]v\![/tex] would be negative. Apply the SUVAT equation [tex]v^{2} - u^{2} = 2\, a\, x[/tex] to find [tex]v[/tex] from [tex]u[/tex], [tex]a[/tex], and [tex]x[/tex].
[tex]\begin{aligned}v^{2} &= u^{2} + 2\, a\, x\end{aligned}[/tex].
[tex]\begin{aligned}v &= -\sqrt{u^{2} + 2\, a\, x} \\ &= -\sqrt{(0\; {\rm m\cdot s^{-1}})^{2} + 2\, (-9.81\; {\rm m\cdot s^{-2}})\, (-190\; {\rm m})} \\ &\approx (-61)\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].
(Note that [tex]v[/tex] is negative.)
In other words, the velocity of the vehicle would be approximately [tex](-61)\; {\rm m\cdot s^{-1}}[/tex] at the end of the drop.
What is the mass of a softball if it hit the catcher's glove traveling at
48.7 m/s2 and struck with a force of 51.3-Newton?
Answer:
To solve this problem, you can use the formula F = ma, where F is the force applied to an object, m is the mass of the object, and a is the acceleration of the object. In this case, the force applied to the object is 51.3 newtons and the acceleration of the object is 48.7 m/s2. So, you can set up the equation like this:
51.3 newtons = m x 48.7 m/s2
To solve for the mass of the object, you can divide both sides of the equation by 48.7 m/s2:
51.3 newtons / 48.7 m/s2 = m x 48.7 m/s2 / 48.7 m/s2
This simplifies to:
1.05 kg = m
So, the mass of the softball is approximately 1.05 kilograms.
The motion of a particle is described by x= 10 sin2t + 8cos2t. Determine the period, amplitude and phase angle
Answer:
Explanation:
period is 2pi / B which is 2pi/8 which is 1/4 pi
amplitude is a which is 10
At a _________ light, after checking to the rear, stop before entering the intersection or at the stop bar. If the stop cannot be made safely, proceed through the intersection with caution.
"At a yellow light, after checking to the rear, stop before entering the intersection or at the stop bar." If stopping safely is not possible, cautiously cross the junction.
Devices that are typically located at significant sites, such as busy junctions, are used to give out traffic signals in order to control the flow of traffic.
A yellow traffic light serves as a warning that the red signal will soon be shown. As a result, as soon as you notice a yellow light, you should begin to slow down in preparation for a red light. Additionally, if for some reason you are unable to stop, you should keep an eye out for any vehicles that may be approaching the intersection at the same moment.
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Among the elementary subatomic particles of physics is the muon, which decays within a few microseconds after formation. The muon has a rest mass 206.8 times that of an electron. Calculate the de Broglie wavelength associated with a muon traveling at 8.85 * 105 cm>s
By using the formulae, λ = h/mv, The De Broglie wavelength of the muon is calculated to be 4.13 × 10^10 m, as according to the given data in the question.
Is the nanosecond the shortest?The shortest measured time is 100 attoseconds. A quadrillionth of a minute is a femtosecond. One quadrillionth of a minute is a picosecond. One quadrillionth of a second is a nanosecond.
What is more compact than nano?Particles are smaller than just a nanometer. Depending on the element, an atom is between 0.1 and 0.3 nm in size. Atoms on the a surface in a SEM image.
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To help me become a detective, would it matter if I did triple science or not?
Answer:
No, it would not matter if you did triple science or not in terms of becoming a detective. However, it is important to have a good academic background and a strong understanding of the law and criminal justice system. Additionally, having good communication and problem-solving skills is also beneficial.
Explanation:
20 points!
A student wants to measure the diameter of a ping pong ball, a golf ball, and a baseball.
Which SI unit should the student use?
centimeters
moles
kilometers
milligrams
Answer:
Centimeters.
Explanation:
There are only 2 viable answers here. This is due to the fact that moles are used not to measure diameters but instead the number of atoms.
Similarly, milligrams are not used to measure diameters but instead small volumes.
This leaves us with kilometers and centimeters, and since all 3 objects are more easily representable in centimeters than kilometers, the answer must be centimeters. One example would be the diameter of a ping pong ball, which is approximately 4cm, or in other words, 0.00004km, with 4cm being much more easy to represent as it overall involves less digits.