Consider an exothermic constant volume CSTR with a cooling jacket in which a single second order reaction occurs. The rate constants show an Arrhenius dependency. F and Te are the only input variables. a) Derive the dynamic model for this process. b) Derive the linearized dynamic model in terms of the deviation variables. Focus on con- centration of A and the temperature T c) Write the model using state space representation with both CA and T as output variables

Answers

Answer 1

a) The dynamic model is derived using reaction kinetics and heat transfer principles.

b) The linearized dynamic model is obtained by linearizing the equations around the steady state.

c) The state space representation includes state variables, input variables, and output variables, with the state equations describing the system dynamics and the output equations relating the state variables to the outputs.

How to derive the dynamic model for this process?

a) To derive the dynamic model for the exothermic constant volume CSTR with a cooling jacket, we need to apply the principles of reaction kinetics and heat transfer. Let's consider the following second-order irreversible reaction:

A + B -> C

The rate equation for this reaction can be expressed as:

r = k * CA * CB

where r is the reaction rate, k is the rate constant, CA is the concentration of species A, and CB is the concentration of species B.

The rate constant k follows an Arrhenius dependency and can be written as:

k =[tex]k0 * exp(-Ea / (R * Te))[/tex]

where k0 is the pre-exponential factor, Ea is the activation energy, R is the ideal gas constant, and Te is the temperature of the cooling jacket.

Now, let's derive the dynamic model for the CSTR. The material balance equation for species A can be written as:

[tex]V * dCA/dt = F * (CA_in - CA) - V * r[/tex]

where V is the volume of the reactor, F is the volumetric flow rate, and [tex]CA_[/tex]in is the concentration of species A in the feed.

Applying the energy balance equation, considering constant volume and neglecting pressure effects, we have:

[tex]V * ρ * Cp * dT/dt = F * ρ * Cp * (T_in - T) + ΔHr * V * r - UA * (T - Te)[/tex]

where ρ is the density, Cp is the heat capacity, T is the temperature of the reactor, T_in is the temperature in the feed, ΔHr is the heat of reaction, UA is the overall heat transfer coefficient, and (T - Te) represents the temperature difference between the reactor and the cooling jacket.

By substituting the expression for r and rearranging the equations, we obtain the dynamic model for the exothermic constant volume CSTR with a cooling jacket.

How to derive the linearized dynamic model in terms of the deviation variables?

b) To derive the linearized dynamic model in terms of the deviation variables (perturbations from the steady-state), we consider the following deviation variables:

ΔCA =[tex]CA - CA_ss[/tex]

ΔT = [tex]T - T_ss[/tex]

where CA_ss and T_ss are the steady-state concentrations of species A and temperature, respectively.

Linearizing the dynamic model equations around the steady-state conditions, we obtain:

[tex]V * d(ΔCA)/dt = -V * (dCA_ss/dt) - (F/V) * ΔCA - V * (∂r/∂CA) * ΔCA - V * (∂r/∂CB) * ΔCB[/tex]

[tex]V * ρ * Cp * d(ΔT)/dt = -V * ρ * Cp * (dT_ss/dt) - (F/V) * ΔT + ΔHr * V * (∂r/∂CA) * ΔCA + ΔHr * V * (∂r/∂CB) * ΔCB - UA * ΔT[/tex]

where (∂r/∂CA) and (∂r/∂CB) are the partial derivatives of the reaction rate with respect to the concentrations of species A and B, respectively.

How to find the model using state space representation?

c) The state-space representation of the dynamic model with both CA and T as output variables can be written as follows:

State variables:

x1 = ΔCA

x2 = ΔT

Input variables:

u1 = F

u2 = Te

Output variables:

y1 = CA

y2 = T

The state equations can be written as:

[tex]dx1/dt = (-1 / τ_CA) * x1 + (1 / τ_CA) * u1 + (1 / τ_CA) * (Δr / ΔCA) *[/tex]

Learn more about  dynamic modeling

brainly.com/question/2285882

#SPJ11


Related Questions

what is the basic concept of the finite element method.​

Answers

Answer:

The FEM is a general numerical method for solving partial differential equations in two or three space variables (i.e., some boundary value problems). To solve a problem, the FEM subdivides a large system into smaller, simpler parts that are called finite elements.

Write a class having two private variables and one-member function which will return the area of the rectangle.

Answers

Using the knowledge in computational language in C++ it is possible to write the code being write a class having two private variables

Writting the code in C++:

#include <iostream>

using namespace std;

class Rectangle { /*create a class named Rectangle*/

  private:

  float l,b; /*this class has two private variables l and b*/

  public:

  float getArea(float l, float b) /*this class has one member-function getArea which returns the area of the rectangle*/

  {

   return l*b; /*return the area of the rectangle*/

  }

};

int main () { /*the main function to check the working of our Rectangle class*/

 float l,b;

 Rectangle r1; /*create an object r1 of Rectangle class*/

 cout<<"Enter the length of the rectangle: ";

 cin>>l; /*input the length of the rectangle from the user*/

 cout<<"Enter the breadth of the rectangle: ";

 cin>>b; /*input the breadth of the rectangle from the user*/

 cout <<"Area of the rectangle is: "<< r1.getArea(l,b)<<" square units."; /*find the area of the rectangle using the member function of the class*/

 return 0;

}

See more about C++ at brainly.com/question/19705654

#SPJ1

The advantage of using a reference line to position a building is that

Answers

Answer:

The reference line helps you achieve the precise connection of Walls for clean intersections.

Explanation:

Reference Lines allow you to place lines on the plot at specific locations to mark important values. You could use these to mark control limits or to indicate a trend line for a set of data.

Through Engineering, human achievement continues to advance. Write about your favorite example of engineering in action and what impresses you about it from an Engineering standpoint.

Answers

Hydroelectric power plants are outstanding engineering devices that allow people to obtain energy from renewable sources.

What is a hydroelectric power plant?

A hydroelectric power plant is a center for the production of electricity based on hydropower energy systems.

Hydroelectric power plants exploit the energy of water masses (e.g., a stream) to produce clean energy for million of people around the world.

These plants have generators capable of converting mechanical energy  into electricity by using simple turbines.

In conclusion, hydroelectric power plants are outstanding engineering devices that allow people to obtain energy from renewable sources.

Learn more about Hydroelectric power plants here:

https://brainly.com/question/8934285

#SPJ1

Which load balancing method is supported in equal cost multipath (ECMP) load balancing when SD-WAN is enabled

Answers

Volume load balancing method is supported in equal cost multipath (ECMP) load balancing when SD-WAN is enabled.

What is load balancing method?

Load balancing means are regarded as a form of an algorithms or method that is used to rightly share an incoming server request or traffic in the midst or among servers that is from the server pool.

Note that Volume load balancing method is supported in equal cost multipath (ECMP) load balancing when SD-WAN is enabled as that is its role.

Learn more about Volume load balancing from

https://brainly.com/question/28021339

#SPJ1

An important difference between expressways and freeways is that expressways feature intersections, whereas freeways use: a) interchanges b) medians c) rumble strips d) green guide signs

Answers

An important difference between expressways and freeways is that expressways feature intersections, whereas freeways use a) interchanges.

What is the mode of operation of a ramp digital voltimeter​

Answers

Answer:

The operating principle of a ramp type digital voltmeter is to measure the time that a linear ramp voltage takes to change from level of input voltage to zero voltage (or vice versa).

How are new slip rings attached to the rotor core during alternator rebuilding?

Answers

The new slip rings is been  attached to the rotor core during alternator rebuilding by b. Soldered on.

What is the process of Soldering ?

Soldering  is the use of Solder which is a metal alloy  consisting tin and lead and is the way of joining  different types of metals together by melting solder.

This is been used on new slip rings to get it  attached to the rotor core during alternator rebuilding .

Learn more about Soldering on:

https://brainly.com/question/25759088

#SPJ1

CHECK THE COMPLETE QUESTION BELOW:

How are new slip rings attached to the rotor core during alternator rebuilding?

a. Machine clamped

b. Soldered on

c. Crimped on

d. epoxy glue

Technician A says that a voltage drop on the ground side of a bulb won’t affect its brightness because the electricity has already been used up. Technician B says that a voltage drop is one way to determine if there is unwanted resistance in a circuit. Who is correct?

Answers

Answer:

  Technician B

Explanation:

For a given circuit current, the voltage drop is an indication of the resistance in the circuit.

If the voltage drop on the ground side of a bulb is unexpectedly high, it means the circuit resistance is unexpectedly high. Technician B is correct.

The only difference between all GMA welding machines and some FCA welding machines is that all GMA welding machines must have a ______________.

Answers

Answer: Shielding gas solenoid

Explanation:

Vivian's Violins has sales of $326,000, contribution margin of $184,000 and fixed costs total $85,000. Vivian's Violins net operating income is Blank______. Multiple choice question. $241,000 $57,000 $99,000

Answers

Based on the calculations, Vivian's Violins net operating income is equal to: D. $99,000.

How to calculate net operating income?

Mathematically, the net operating income of an individual or business firm can be calculated by using this formula:

Net operating income = Contribution margin - Total fixed costs

Given the following data:

Sales = $326,000Contribution margin = $184,000Fixed costs total $85,000

Substituting the given parameters into the formula, we have;

Net operating income = $184,000 - $85,000

Net operating income = $99,000.

Read more on net operating income here: https://brainly.com/question/24165947

#SPJ1

Assignment: Explain any three
ways that research can facilitate
the work of building technicians.

Answers

The three ways that research can facilitate the work of building technicians is that:

They will know the timeframe to start and complete the buildingThey will know the type and right materials to use.It will help them in the area of budgeting of equipment, tools and building materials needed.

What do building technicians do?

Building technicians are known to be people who help with some tasks around construction projects and building works.

Note that building technician overseeing a scope of tasks such as monitoring build progress and as such The three ways that research can facilitate the work of building technicians is that:

They will know the timeframe to start and complete the buildingThey will know the type and right materials to use.It will help them in the area of budgeting of equipment, tools and building materials needed.

Learn more about technicians from

https://brainly.com/question/1548867

#SPJ1

In 2001, a land-development company launched an engineering project on land adjacent to a protected wetlands area

Answers

The statement that summarizes the data is that the population data should be collected over a much lingers period of time in order to draw a valid conclusion.

What is data?

It should be noted that data simply means the facts or statistics that are put together to get more information about a particular issue.

It should be noted that a project simony refers to an individual or collaborative enterprise which is planned in order to achieve a particular aim. In this case, the land-development company launched an engineering project on land adjacent to a protected wetlands area.

It should be noted that the time frame that the data was collected matters a lot in order to get a valid conclusion.

In this case, the statement that summarizes the data is that the population data should be collected over a much lingers period of time in order to draw a valid conclusion.

Learn more about data on:

brainly.com/question/4219149

#SPJ1

The options to the question:

a. The data Gail to represent a broad diversity of species and so do not provide enough information to adequately draw a conclusion.

b. Population data were not sampled frequently enough to draw a valid conclusion.

c. The data show stable population trends in native species providing evidence that the engineering project has no negative impact on the ecosystem.

d. The population data should be collected over a much lingers period of time in order to draw a valid conclusion.

a. Calculate the equivalent resistance of the circuit

Answers

Answer:

no any think photo.

Explanation:

If extension done in a stork position, during backward bending in a standing position of a special test for lumbar spine, produces pain in the lumbar or sacral regions of the spine, it may indicate _____.

Answers

The answer is 7 because I just took the test!

A handsfree device may be used if it can be activated or deactivate with a?

Answers

A handsfree device may be used if it can be activated or deactivate with a cellphone.

What is hands-free?

Handsfree is a device which when connected to a cell device can be used in listening to audio, video and messages.

A driver can also activate or deactivate with a swipe when connect to the vehicle audio device.

Therefore,

A handsfree device may be used if it can be activated or deactivate with a cellphone.

Learn more on handsfree below

https://brainly.com/question/12253610

#SPJ1

An isolation transformer whose main purpose is to reduce voltage spikes will have a turns ratio of?

Answers

Answer:

An isolation transformer whose main purpose is to reduce voltage spikes will have a turns ratio of 1 to 1.

This is due to the windings input and output having the same waveform and amplitude.

based on the graph shown, for any given output level, the veritcal distance between the avc and the atc curves represents

Answers

A a result of the graph shown, for any given output level, the veritcal distance between the avc and the atc curves represents total fixed cost (TFC).

What is Vertical distance?

This is known as vertical separation and it is said to be the distance that exist between two vertical positions.

Note that vertical coordinates are seen for expressing vertical position: depth, and others and as such,

See full question below

The vertical distance between the ATC and AVC curve represents

a) marginal cost (MC)

b) average fixed cost (AFC)

c) total fixed cost (TFC)

d) total cost (TC) - total variable cost (TVC)

Learn more about from

https://brainly.com/question/210650

#SPJ1

Modern aircraft are designed in a way that, when all seats are occupied, the baggage compartment is full, and all fuel tanks are full, the aircraft is:

Answers

Modern aircraft are designed in a way that, when all seats are occupied and baggage is full, and all fuel tanks are full, the aircraft is overloaded.

What is aircraft storage?

Aircraft storage refers to all storage systems in an aircraft for human transportation and also to transport products among countries.

The aircraft storage system is well calculated to work is a maximum capacity in commercial fly lines.

In conclusion, modern aircraft are designed in a way that, when all seats are occupied and baggage is full, and all fuel tanks are full, the aircraft is overloaded.

Learn more about storage systems here:

https://brainly.com/question/9585033

#SPJ1

The lights on your vehicle must be turned on at any time, day or night, when persons and vehicles cannot be clearly seen for ___ feet.

Answers

Answer:

500 feet

Explanation:

In order to stop or turn your vehicle around on the highway you must have 500 feet of clear road in both directions. 4. Headlights are required at any time you cannot see persons or vehicles for 500 feet, due to snow, dust, fog, etc. and from ½ after sunset to ½ before sunrise.Hope this helps

The lights on your vehicle must be turned on at any time, day or night, when persons and vehicles cannot be clearly seen for 1000 feet.

What are vehicles?

A vehicle is a piece of equipment, typically with wheels and an engine, used for land-based transportation of people or goods. Cars, buses, and trucks are examples of road vehicles. Farm vehicles include tractors.

Vehicle type refers to a group of power-driven vehicles that share all crucial aspects of their engines, cars, and OBD systems.

When a vehicle is 500 feet away, the driver must dim his headlights.

Avoid looking directly into the light when a car is coming at you; instead, slow down. At least 30 minutes before dusk, headlights must be activated. It is also important to keep in mind that a lower headlight beam improves the driver's ability to see in fog.

Thus, it should be 1000 feet distance.

For more details regarding vehicles, visit:

https://brainly.com/question/29491014

#SPJ2

If your crew is the first to arrive on the scene of a major mci, what will be a major aspect of your scene size-up?

Answers

If your crew is the first to arrive on the scene of a major MCL, The major aspect of your scene size-up will be to Make a sweep to determine what needs must be met. Option D. This is further explained below.

What is the scene of an MCL?

Generally, If your team is the first to arrive at the scene of a significant MCL, the most important part of your scene size-up will be to do a sweep to identify the requirements that need to be satisfied. Choose option D.

In conclusion, A medial collateral ligament (MCL) injury occurs when the ligament on the inside of the knee is stretched, partially torn, or completely ruptured. Most knee injuries are caused by an excessive amount of valgus stress on the knee, which is one of the most prevalent.

Read more about the scene of an MCL

https://brainly.com/question/13184254

#SPJ1

CQ

If your crew is the first to arrive on the scene of a major​ MCI, what will be a major aspect of your scene​ size-up?

A.

Make an initial scene report to the communications center.

B.

Control​ on-scene communication as help arrives.

C.

Prevent uncoordinated or undirected activity at the scene.

D.

Make a sweep to determine what needs must be met.

Metal wireways are sheet metal troughs with _____________ for housing and protecting electrical conductors and cable.

Answers

Answer:

Metal wireways are sheet metal "U"s with removable housing for protecting electrical equipment, wires, and cables.

Explanation:

These are especially used to run wire in manufacturing environments.

A light weight vehicle traveling 50 mph can stop in approximately
a. 200 meters.
b. 5 blocks.
c. 200 feet.
d. 6 seconds.

Answers

A light weight vehicle traveling 50 mph can stop in approximately 200 feet.

How a car break works?

The break system of a car is composed by several items that are always working together to slow down and bring a vehicle to a complete stop. It also has the function of keeping the car stationary when it is parked. In general, this system has two manual activation modes: the lever and the pedal, with the exception of vehicles adapted for people with disabilities.

Most vehicles today use the disc brake system. Disc brakes work by using pads, which are held inside a hydraulic caliper, receiving pressure to brake. Such pads generate friction on a disc, which makes the vehicle stop permanently.

The drum brake is another type, being older and dependent on the famous linings to cause friction in the wheel and stop the vehicle. A hydraulic cylinder makes the plies move inside the drum, which is a hollow part fastened with screws and attached to the wheels. This type of brake is on the rear wheels, for the most common models.

See more about engineering at: brainly.com/question/19117846

#SPJ1

Which is not one of the primary characteristic of unit testing:

Answers

Answer:

Unit testing is a software development process in which the smallest testable parts of an application, called units, are individually and independently scrutinized for proper operation. This testing methodology is done during the development process by the software developers and sometimes QA staff. The main objective of unit testing is to isolate written code to test and determine if it works as intended.

Unit testing is an important step in the development process, because if done correctly, it can help detect early flaws in code which may be more difficult to find in later testing stages.

Unit testing is a component of test-driven development (TDD), a pragmatic methodology that takes a meticulous approach to building a product by means of continual testing and revision. This testing method is also the first level of software testing, which is performed before other testing methods such as integration testing. Unit tests are typically isolated to ensure a unit does not rely on any external code or functions. Testing can be done manually but is often automated. It might be helpful

Structural Safety Assessment and Traffic Control Strategies of Widened Highway Bridges under Maintenance Works Requiring Partial Lane Closure

Answers

Structural Safety Assessment and Traffic Control Strategies of Widened Highway Bridges under Maintenance Works Requiring Partial Lane Closure journal is based on the  way and techniques that can be used in maintaining  the Safety on the road as well as the Assessment of Traffic Control.

What are the techniques in controlling the traffic?

There are Devices that are typically used in the traffic control, and this can  include speed bumps as well as the barricades to block streets.

Others techniques are:

turn prohibitions stop signs raised pavement markers.

Traffic restraint can also entails the includes programs  that can foster bicycle as well as the pedestrian travel.

The rapid structural safety assessment help in inspecting and evaluating the concrete structure as well in determining  the damaged structure if it is  unsafe for personnel within the building .

Learn more about Traffic Control at:

https://brainly.com/question/26052026

#SPJ1

P=3000W
f1=0.9
f2=0.5
A=15mm2
travel speed=?

Answers

The Travel Speed at which the welding operation can be accomplished is given as 7.147mm/s. See the computation below.

What is travel speed?

The travel speed of the welding flame or gun across the workpiece is simply measured in millimeters per minute.

Travel speed, along with voltage and amperage, is one of three factors in arc welding that affect the amount of heat input.

What is the calculation that justifies the above answer is?

We are given the following:


Melting temperature = 1650 K

k = (3.33 * 10⁻⁶) * (1,650)²

k = 9.066 J/mm^3

The formula for velocity here is given as:

V = f1 * f2 * Rh / (k*A)

V = 0.9 * 0.6 * 3000 / (9.066*25)

V = 7.147 mm/s

Hence, the Travel Speed at which the welding operation can be accomplished is given as 7.147mm/s.

Learn more about welding operation at;
https://brainly.com/question/22494632
#SPJ1

When passing another car, make sure you maintain at least a _______ safety cushion

Answers

The answer is 4 because I just took the test!

Someone claims that the volume flow rate in a circular pipe with laminar flow can be determined by measuring the velocity at the centerline in the fully developed region, multiplying it by the cross-sectional area, and dividing the result by 2. Do you agree

Answers

The answer is 6 because I just took the test!

To put out a class D metal fire, you must _______ the fire.

Answers

To put out a class D metal fire, you must smother the fire and eliminate the oxygen element in the fire.

What is a Class D fire?

A class D fire is a type of fire that cannot be extinguished by water. This is because adding water to it reacts with other elements in the fire intensifying the fire even more.

Smothering in this context involves adding a solution like carbon dioxide (CO2) into the fire, this results in a reduction of oxygen in the atmosphere surrounding the class D fire.

By so doing, smothering the fire eliminates the oxygen element in the fire, thereby extinguishing the fire.

You can learn more about extinguishing fires here https://brainly.in/question/760550

#SPJ1

Determine the carburizing time necessary to achieve a carbon concentration of 0.30 wt.% at a position of 4 mm into an iron-carbon alloy that initially contains 0.10 wt.% C. The surface concentration is to be maintained at 0.90 wt.% C, and the treatment is to be conducted at C. Use the diffusion data for -Fe in Table 5.2

Answers

The carburizing time necessary to achieve a carbon concentration is 31.35 hours

How to find the Carburizing Time?

To determine the carburizing time necessary to achieve the given carbon concentration, we will use the equation:

(Cs - Cx)/(Cs - C0) = ERF(x/2√Dt)

where;

Cs is Concentration of carbon at surface = 0.90

Cx is Concentration of carbon at distance x = 0.30

Distance x = 4 mm = 0.004 m

C0 is Initial concentration of carbon = 0.10

ERF() = Error function at the given value

D = Diffusion of Carbon into steel

t = Time necessary to achieve given carbon concentration ,

Thus, plugging in the relevant values gives;

(Cs - Cx)/(Cs - C0) = (0.9 - 0.3)/(0.9 - 0.1)

= 0.6/0.8 = 0.75

now, ERF(z) = 0.75 and as such using ERF table, we can say that;

Z = 0.814. Thus;

(x/2√Dt) = 0.81

Using the table of diffusion data, we have;

At a temperature of  (1100°C) or 1373 K, we have;

D = 5.35 × 10⁻¹¹ m²/sec.

Calculating the carbonizing time by using the equation z = (x/2√Dt);

where;

t is carbonizing time

Thus;

0.814 = (0.004/(2 × √5.35 × 10⁻¹¹ × √t))

0.814 = 0.004 /(1.4628 × 10⁻⁵ × √t)

0.814 × 1.4628 × 10⁻⁵ × √t = 0.004

1.19072 × 10⁻⁵ × √t = 0.004  

√t = 0.004/(1.19072 × 10⁻⁵)

√t = 335.93

t = 112848.96 seconds

Converting to hours gives;

t = 112848.96/3600

t = 31.35 hours

Therefore, the carburizing time necessary to achieve a carbon concentration is 31.35 hours

Read more about Carburizing Time at; https://brainly.com/question/13031810

#SPJ1

Other Questions
Which belongs in each blank ? Choose the vocabulary word that best fits in each blank El trama, Seran La ladrona un fracaso Violencia Write an Objective Summary Of The Battle Of Mr.Covey by Fredrick Douglass. which is a common denominator of 1/4 and 3/5? and A. 9 B. 15 C. 16 D. 20 Question 4 of 18Which sentence order creates the most logical sequence for an introductoryparagraph?Sentence A: Though there are benefits to enjoying the sunshine, theharmful effects of long-term sun exposure can be very serious.Sentence B: How many times has a fun day at the beach ended with apainful sunburn?Sentence C: Sunburns are caused by exposure to UV rays, which insmall doses can provide the body with essential nutrients like vitaminD. But overexposure to UV rays can cause skin damage and, in extremecases, skin cancer. Find the smaller angle (in degrees) between the hands of a clock at 3:25. How should I start off a poem about deforestation The water cycle describes the movement of water on Earth. Water in oceans and lakes evaporates and turns into water vapor. This water vapor condenses and forms clouds which produce precipitation. Precipitation falls all over the Earth's surface. The water eventually comes back to the oceans through run-off. Which steps in the water cycle carry water out of an ocean and into a freshwater lake?A. Evaporation and precipitationB. Rivers and streamsC. Underground tunnelsD. Condensation and run-off 300,000,000 m/s is the speed of ? What is 0.8 simplified to a fraction? SHOW YOUR WORK/SHOW HOW YOU GOT YOUR ANSWERElla has $35 in her bank account. She deposited a check for $140 and then withdrew $80. How much money is left in her bank account? pls help. this is romeo and juliet Show set of data that is a function using at least 5 domain values and 5 range values. It can be shown in a format of your choice (graph, table, set notation). Round the 136.501 to the whole number. find the value of x?? 14. If 100 grams of sodium nitrate are dissolved in 100 grams of waterat 60 degrees C, is the solution formed saturated, unsaturated, orsupersaturated? thank u it really helped Find the slope. hsjsnsjsbjabajabahabh Which of the following has tooccur in order for mammals tocreate offspring?A. fertilizationB. self-reproductionC. mutationD. self-fertilization Plz help due tomorrow The tell tale heart Summarize the text. List five to seven key events from the story in the order in whichthey happen. Your summary should include main points from the beginning, middle,and end of the story.