Assume that​ women's heights are normally distributed with a mean given by mu = 64.3 inches​, and a standard deviation given by sigma= 2.2 inches.
A) If a woman is randomly selected, find the probability that her height is less than 65 inches.
B) If 34 women are randomly selected, find the probability that they have a mean height less than 65 inches.

Answers

Answer 1

Answer:69

Step-by-step explanation:


Related Questions

According to the Federal Communications Commission, 70% of all U.S. households have vcrs. In a random sample of 15 households, what is the probability that fewer than 13 have vcrs?

Answers

Answer:

The probability  is  [tex]P(x < 13) = 0.8732[/tex]

Step-by-step explanation:

From the question we are told that

    The  probability of success is    p = 0.70

     The  sample size is  [tex]n = 15[/tex]

Generally the distribution of U.S. households have vcrs follow a binomial distribution given that there are only two outcome (household having vcrs or household not having vcrs )

The probability of failure is mathematically evaluated as

       [tex]q = 1- p[/tex]

substituting values

      [tex]q = 1- 0.70[/tex]

      [tex]q = 0.30[/tex]

The probability that fewer than 13 have vcrs is mathematically represented as

          [tex]P(x < 13) = 1- [P(13) + P(14) + P(15)][/tex]

=>     [tex]P(x < 13) = 1-[( \left 15 } \atop {}} \right. C_{13} *p^{13}* q^{15-13})+ (\left 15 } \atop {}} \right. C_{14} *p^{14}* q^{15-14}) +( \left 15 } \atop {}} \right. C_{15} *p^{15}* q^{15-15}) ][/tex]

 Here  [tex]\left 15 } \atop {}} \right. C_{13}[/tex] means  15 combination 13 and the value is  105 (obtained from calculator)

 Here  [tex]\left 15 } \atop {}} \right. C_{14}[/tex] means  15 combination 14 and the value is  15 (obtained from calculator)

 

 Here  [tex]\left 15 } \atop {}} \right. C_{15}[/tex] means  15 combination 15 and the value is  1 (obtained from calculator)

So

 [tex]P(x < 13) = 1-[(105 *p^{13}* q^{2})+ (15 *p^{14}* q^{1}) +(1*p^{15}* q^{0}) ][/tex]

substituting values      

 [tex]P(x < 13) = 1-[(105 *(0.70)^{13}* (0.30)^{2})+ (15 *(0.70)^{14}* (0.30)^{1}) +(1*(0.70)^{15}* (0.30)^{0}) ][/tex]

 [tex]P(x < 13) = 0.8732[/tex]

     

a theater has (2x+1) rows of seats, with (x-3) seats in each row. how many seats are in the theater?
A. 2x^2- 5x- 3
B. 2x^2+ 5x- 3
C. 2x^2- 7x+ 3
D. 2x^2- 7x- 3

Answers

the answer would be B hope it’s right

(2x+1)(x-3)

y(x-3) .... let y = 2x+1

y*x+y(-3) .... distribute

xy - 3y

x( y ) - 3( y )

x( 2x+1 ) - 3( 2x+1) ... replace y with 2x+1

2x^2 + x - 6x - 3 ..... distribute

2x^2 - 5x - 3

Answer is choice A

In a triangle ABC,AB=9 and BC =12 which of the following Cannot be the length of AC.

Answers

Step-by-step explanation:

mark it as the brainliest

Answer:

i need help with this too

Step-by-step explanation:

How many gallons of a 5% bleach solution must be
added to 10 Gallons of a 20% bleach solution to
produce that is 15% bleach

Answers

Answer:

Step-by-step explanation:

10 gallons of the 20% solution contain 2 gallons of bleach.

x gallons of the 5% solution contain 0.05x gallons of bleach.

If the two are combined, the resulting 10+x gallons contain 2+0.5x gallons of bleach. The concentration is (2+0.05x)/(10+x).

(2+0.05x)/(10+x) = 15%

2+0.05x = 0.15(10+x)

2+0.05x = 1.5+0.15x

0.5 = 0.10x

x = 5

5 gallons of 5% solution is added to the 10 gallons of 20% solution.

a radion station usa 1\6 of its time for the news. in a 12 hour day, how many hours are used for music & entertainment?

Answers

Answer:

  10 hours

Step-by-step explanation:

In order to answer this question, you must assume that all air time not spent on news is spent on music & entertainment. That would usually not be the case, as there would usually be advertisements and public service programming along with everything else.

The time spent on news is ...

  (1/6)(12 hours) = 2 hours

If the rest is spent on music and entertainment, then ...

  12 -2 = 10 . . . hours are used for music and entertainment

An octagonal pyramid ... how many faces does it have, how many vertices and how many edges? A triangular prism ... how many faces does it have, how many vertices and how many edges? a triangular pyramid ... how many faces does it have, how many vertices and how many edges?

Answers

1: 8 faces and 9 with the base 9 vertices and 16 edges

2: 3 faces and 5 with the bases 6 vertices and 9 edges

3: 3 faces and 4 with the base 4 vertices and 6 edges

Hope this can help you.

1: 8 faces and 9 with the base 9 vertices and 16 edges

2: 3 faces and 5 with the bases 6 vertices and 9 edges

3: 3 faces and 4 with the base 4 vertices and 6 edges

find the missing side. round your answer to the nearest tenth. PLEASE HURRY!

Answers

Answer:

44.8

Step-by-step explanation:

Using the Cosine formula, we first have Cos 48 = 30/x. So then we just solve for x and get 44.8342965, which rounds to 44.8

I hope this helped! :D

What is the lateral surface area of a right hexagonal prism whose base is a regular hexagon with sides measuring 8 inches long and altitude measuring 6 inches tall?

Answers

Answer:

  288 square inches

Step-by-step explanation:

Assuming your "altitude" is the height of the prism--the distance between bases, the lateral area is the sum of the areas of the six rectangular faces. Each of those has an area of ...

  (8 in)(6 in) = 48 in^2

so the 6 of them will have an area of ...

  lateral area = 6×48 in^2 = 288 in^2

_____

Comment on nomenclature

'Altitude' is usually associated with the height of a triangle. In the case of a regular polygon, the 'altitude' of a triangular section of the polygon is called the 'apothem', and is often designated using the letter 'a'. If the polygon is regular, the apothem can be calculated from the side length and the number of sides, but it is often given in problems involving area, perimeter, and/or volume.

The distance between the parallel bases of a prism is often referred to as the prism height or length. The use of the word 'altitude' is confusing in this case.

Since the lateral area is the product of the perimeter of the base and the distance between bases, we have to assume that your 'altitude' refers to the distance between bases. Otherwise, there is not sufficient information to work the problem.

What is the constant of variation, k, of the direct variation, y = kx, through (–3, 2)?


k = –k equals negative StartFraction 3 Over 2 EndFraction.

k = –k equals StartFraction 2 Over 3 EndFraction.

k = k equals StartFraction 2 Over 3 EndFraction.

k = k equals StartFraction 3 Over 2 EndFraction.

Answers

Answer:

k = 2/-3

Step-by-step explanation:

y = kx

Point: (-3, 2)

2 = k(-3)

k = 2/-3

k = -0.6

Answer: k = 2/-3

Step-by-step explanation: Option (B)

Taking the test as we speak

Yuko added a 15 percent tip when she paid her cab driver. If the fare was $25.50, what was the total amount she paid? A. $28 B. $30 C. $31

Answers

Answer:

B. $30

Step-by-step explanation:

First, find the amount of the tip.

Multiply the tip rate and taxi fare.

tip rate * taxi fare

The tip rate is 15% and the taxi fare is $25.50

15% * 25.50

Convert 15% to a decimal. Divide 15 by 100 or move the decimal place two spots to the left.

15/100=0.15

15.0 ---> 1.5 ---> 0.15

0.15 * 25.50

3.825

The tip amount is $3.825

Next, find the total amount she paid.

Add the taxi fare and the tip amount.

taxi fare + tip amount

The taxi fare is $25.50 and the tip amount is $3.825

$25.50 + $3.825

$29.325

Round to the nearest dollar. Typically, this would round down to $29, but that is not an answer choice. So, if we round up, the next best answer is $30.

Therefore, the best answer choice is B. $30

Find the slope of the line whose x-intercept is 4 and the y- intercept is -9

Answers

Answer:

y = (9/4)x - 9

Step-by-step explanation:

The x-intercept is (4, 0) and the y-intercept is (0, -9).

As we move from (0, -9) to (4, 0), x (the 'run' increases by 4 and y (the 'rise' increases by 9.  Thus, the slope of the line connecting these two points is m = rise/run = 9/4, from which we can write the desired equation in the form y = mx + b:

y = (9/4)x - 9


Factor of
x2 – 14x + 24
A. (x - 6)(x - 4)
B. (x - 8)(x - 3)
C. (x - 12)(x - 2)
D. (x - 24)(x - 1)

Answers

Answer: The answer is C.

Step-by-step explanation:

Hi, there!!!

The answer is option C.

The solution is in picture.

I hope it helps....

Find 900 ÷ 90.
plz help

Answers

Answer:

the answer is 10

Step-by-step explanation:

900 ÷ 90

=> 10 [tex]\sf{}[/tex]

Answer:

The answer is 10.

Step-by-step explanation:

900/90=cut 0 of numerator and denominator then 90 divide by 9 is 10.

Divide. Write the quotient in lowest terms. 3 3/4 ÷ 5/7

Answers

Rewrite 3 3/4 as an improper fraction

3 3/4 = 15/4

Now you have

15/5 / 5/7

When you divide fractions, change the division to multiplication and flip the second fraction over:

15/4 x 7/5

Now multiply the top numbers together and the bottom numbers together:

( 15 x 7) / (4 x 5) = 105/20

Write as a proper fraction:

105/20 = 5 1/4

Answer: 21/4 or 5 1/4

Explanation:
3 3/4 divide by 5/7
= 15/4 x 7/5
= 105/20
= 21/4 or 5 1/4

Question 19 of 20:
Select the best swer for the question
19. The distance from the center of a round table top to the edge of the table top is 4 ft what is the area of the table top

Answers

Answer:

50.26 ft^2

Step-by-step explanation:

Area=pi*r^2

Area=pi*(4)^2=pi*16=50.26

What is the value of x to the nearest tenth?

Answers

Answer:

x=9.6

Step-by-step explanation:

The dot in the middle represents the center of the circle, so therefore, the line that is represented by 16 is the radius. Since that is the radius, the side that is the hypotenuse of the small triangle is also 16, since they have the same distance.

The line represented by 25.6 with x as its bisector shows that when we divide it by 2, the other side of the triangle besides the hypotenuse is 12.8.

Now that we have the two sides of the triangle, we can find the last side (represented by x). Use pythagorean theorem:

[tex]a^2 +b^2=c^2\\x^2+(12.8)^2=16^2\\x^2+163.84=256\\x^2=92.16\\x=9.6[/tex]

The highest attendance at this stadium was in 2007 when 91,547 people attended. The average cost of a ticket was $57. How much money was made on ticket sales for that game?

Answers

Answer:57*91547

Step-by-step explanation:

Please help brainliest will be given

Complete the equation describing how
x and y are related.
x
-1
5
0 1 2 3 4
3 8
V 2
13
18
23
28
y = 5x + [?]
Enter the answer that belongs in [?].

Answers

Answer:

y = 5x + 3

Step-by-step explanation:

When x = 0 y = 3 so the y-intercept will be 3

And the equation is y = 5x + 3 where the slope is 5

g Which of the following is equivalent to P( A|B)? a. P(A and B) b. P(B|A) c. P(A)/P(B) d. None of these choices.

Answers

Answer:

The correct option is D.

But option B is correct if P(A) = P(B).

Step-by-step explanation:

P(A|B) is read as "The probability of A given B".

It is different from the options A, B, and C.

It is equal to option B only if the probability of A is equal to the probability of B. That is P(A|B) = P(B|A) if P(A) = P(B).

Task: Population of a Species

The population of a species in the wild in Asia has been decreasing exponentially since 1980. This function represents the wild population of the species t years after 1980: W(t)=20000(0.95)t.

The Wildlife Refuge Foundation noticed this trend before 1980
and decided to try to help reduce the population decline by
breeding the species in captivity. The graph shows the number
of these animals that have been born in captivity since 1980.

(Note: The function W(t) and the graph are not the same function!)

[15 points] Use the graph to create a function to represent the number of the species that have been born in captivity, C(t).

Answers

Answer:

C(t) = 20t

Step-by-step explanation:

The graph of C(t) appears to be linear

The y intercept is 0

The slope is 200/10 = 20

y = mx+b  where m is the slope and b is the y intercept

y = 20x+0

y = 20x

C(t) = 20t

Answer:

the answer is c (t) = 20 t

Step-by-step explanation:

[tex]\sf{}[/tex]

:,-)

♛┈⛧┈┈•༶♛┈⛧┈┈•༶

Write each expression in a simpler form that is equivalent to the given expression. Let g be a nonzero number. 1/g^1 or 1/g-1

Answers

Answer:

[tex]\boxed{\mathrm{view \: explanation}}[/tex]

Step-by-step explanation:

Apply rule : [tex]a^1 =a[/tex]

[tex]\displaystyle \frac{1}{g^1 } =\frac{1}{g}[/tex]

[tex]\displaystyle \frac{1}{g^{-1}}[/tex]

Apply rule : [tex]\displaystyle a^{-b}=\frac{1}{a^b}[/tex]

[tex]\displaystyle \frac{1}{\frac{1}{g^1 } }[/tex]

Apply rule : [tex]\displaystyle \frac{1}{\frac{1}{a} } =a[/tex]

[tex]\displaystyle \frac{1}{\frac{1}{g^1 } }=g[/tex]

Answer:

[tex]\frac{1}{g^1}[/tex]

= [tex]\frac{1}{g}[/tex]

[tex]\frac{1}{g - 1}[/tex]

= [tex]\frac{g^1}{1}[/tex]

= [tex]\frac{g}{1}[/tex]

= g

Hope this helps!

How to solve this question

Answers

hopefully this answer can help you to answer the next question. can you choose this answer as the brainliest answer and give five stars

the bold answer is incorrect. what is the right answer?

Answers

Answer: first choice

Explanation:

A complementary angle are two angles add up to 90 degree

In a random sample of 380 cars driven at low altitudes, 42 of them exceeded a standard of 10 grams of particulate pollution per gallon of fuel consumed. In an independent random sample of 90 cars driven at high altitudes, 24 of them exceeded the standard. Compute the test statistic for testing if the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard.

Answers

Answer:

The test statistic for testing if the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard is 3.234.

Step-by-step explanation:

We are given that in a random sample of 380 cars driven at low altitudes, 42 of them exceeded a standard of 10 grams of particulate pollution per gallon of fuel consumed.

In an independent random sample of 90 cars driven at high altitudes, 24 of them exceeded the standard.

Let [tex]p_1[/tex] = population proportion of cars driven at high altitudes who exceeded a standard of 10 grams.

[tex]p_2[/tex] = population proportion of cars driven at low altitudes who exceeded a standard of 10 grams.

So, Null Hypothesis, [tex]H_0[/tex] : [tex]p_1\leq p_2[/tex]      {means that the proportion of high-altitude vehicles exceeding the standard is smaller than or equal to the proportion of low-altitude vehicles exceeding the standard}

Alternate Hypothesis, [tex]H_A[/tex] : [tex]p_1>p_2[/tex]      {means that the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard}

The test statistics that will be used here is Two-sample z-test statistics for proportions;

                             T.S.  =  [tex]\frac{(\hat p_1-\hat p_2)-(p_1-p_2)}{\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+\frac{\hat p_2(1-\hat p_2)}{n_2} } }[/tex]  ~  N(0,1)

where, [tex]\hat p_1[/tex] = sample proportion of cars driven at high altitudes who exceeded a standard of 10 grams = [tex]\frac{24}{90}[/tex] = 0.27

[tex]\hat p_2[/tex] = sample proportion of cars driven at low altitudes who exceeded a standard of 10 grams = [tex]\frac{42}{380}[/tex] = 0.11

[tex]n_1[/tex] = sample of cars driven at high altitudes = 90

[tex]n_2[/tex] = sample of cars driven at low altitudes = 380

So, the test statistics =  [tex]\frac{(0.27-0.11)-(0)}{\sqrt{\frac{0.27(1-0.27)}{90}+\frac{0.11(1-0.11)}{380} } }[/tex]      

                                   =  3.234

The value of z-test statistics is 3.234.

A recent survey asked 1200 randomly selected U.S. adults if they believe that the U.S. federal government is doing enough to keep U.S. elections safe from outside interference. After analyzing the results, the researchers were able to state that they are 95% confident that between 52.5% and 59.5% of all U.S. adults believe that the U.S. federal government is not doing enough to keep U.S. elections safe. Which statement BEST describes how to interpret these results

Answers

Complete Question

The  complete question is shown on the first uploaded image

Answer:

The correct option is  D

Step-by-step explanation:

From the question the question we are told that

    The researchers were able to state that they are 95% confident that between 52.5% and 59.5% of all U.S. adults believe that the U.S. federal government is not doing enough to keep U.S. elections safe.

Generally a confidence interval states to what extent the chances of the true population is within the a given range

 So the 95% confidence interval given in the question as 52.5% and 59.5%  means that the chances of the true population mean being with this given range is 95%

 So given that the the true population mean is within this range then it means that the population mean will be greater than 50%

   So  the statement that best describe and interprets this result is

The results show significant statistical support that most U.S. adults (over 50%) believe that the U. S. Federal government is not doing enough to keep U.S. election safe.

Someone help me understand

Answers

Answer:

f¯¹(x) = 23/ (6x + 3)

Step-by-step explanation:

f(x) = (23 – 3x)/6x

The inverse, f¯¹, for the above function can be obtained as follow:

f(x) = (23 – 3x)/6x

Let y be equal to f(x)

Therefore, f(x) = (23 – 3x)/6x will be written as:

y = (23 – 3x)/6x

Next, interchange x and y.

This is illustrated below:

y = (23 – 3x)/6x

x = (23 – 3y)/6y

Next, make y the subject of the above expression. This is illustrated below:

x = (23 – 3y)/6y

Cross multiply

6xy = 23 – 3y

Collect like terms

6xy + 3y = 23

Factorise

y(6x + 3) = 23

Divide both side by (6x + 3)

y = 23/ (6x + 3)

Finally, replace y with f¯¹(x)

y = 23/ (6x + 3)

f¯¹(x) = 23/ (6x + 3)

Therefore, the inverse, f¯¹, for the function f(x) = (23 – 3x)/6x is

f¯¹(x) = 23/ (6x + 3)

If Tristan wants to stretch the spring by 9 inches, how many kilograms of weight must he apply to it? I need help with it please.

Answers

Answer:

9/3 = 3x/3

3 = x

The spring stretches 9 inches with 3 kilograms of weight attached to it

Step-by-step explanation:

Substitute y = 9 into the equation y = 3x, or locate the answer on the graph:

y = 3x

9 = 3x.

Divide both sides of the equation by 3

Answer:The spring stretches 9 inches with 3 kilograms of weight attached to it.

Step-by-step explanation:

Substitute y = 9 into the equation y = 3x, or locate the answer on the graph:

y = 3x

9 = 3x.

Divide both sides of the equation by 3:

   

The spring stretches 9 inches with 3 kilograms of weight attached to it.

Find the measure of a.

A. 20
B. 70
C. 80
D. 40

Answers

i think it’s 80 :) hope this helps

A circle is a curve sketched out by a point moving in a plane. The measure of a is 70°. The correct option is B.

What is a circle?

A circle is a curve sketched out by a point moving in a plane so that its distance from a given point is constant; alternatively, it is the shape formed by all points in a plane that are at a set distance from a given point, the centre.

In the given circle, the line AC is the diameter of the circle, therefore, the measure of ∠ABC will be 90°.

∠ABC = 90°

This is because a triangle formed on the diameter of the circle such that all the vertices of the triangle intersect the circle, then the angle opposite to the diameter is a right angle.

Now, in ΔABC, the sum of all the angles of the triangle can be written as,

∠ABC + ∠BCA + ∠BAC = 180°

90° + a + 20° = 180°

110° + a = 180°

a = 180° - 110°

a = 70°

Hence, the measure of a is 70°.

Learn more about Circle:

https://brainly.com/question/11833983

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find the HCF of 72,108 and 180​

Answers

Answer:

36 is the answer

Step-by-step explanation:

Answer:

36

Step-by-step explanation:

72: 2×2×2×3×3

108: 2×2×3×3×3

180: 2×2×3×3×5

here, common factors are 2,2,3 and 3 ..

so.. HCF: 2×2×3×3

•°•HCF=36 ..

a lottery offers one $1000 prize one $500 and two $50 prizes. one thousand tickets are sold at $2.50. what is the expectived profit

Answers

Answer:

 $900

Step-by-step explanation:

To begin with let us estimate the total cash value of the prices

$1000 x 1= 1000

$500 x 1=  500

$50 x 2= 100

Total = $1600

Now let us calculate the total cost of tickets sold at $2.50 per tickets for 1000 tickets

2.5*1000= $2,500

Assuming worse case that the lottery had winners in all three categories and i.e the total prices given out is $1600

Then the expected profit is = $2,500-$1600= $900

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if you convinced your friend to lend you her notes to study for an exam, what would this situation be an example of? Fill in the blanks and explain the pattern.1, 4, 9, 16, 25,__,__,__,__,100Fill in the blanks and explain the pattern.1/2, 1/6, 1/18, 1/54,__,__,__ If a company from Country A decides to sell merchandise to a company from Country B, then the company from Country A ________. Should people who resist arrest still face charges if they are ultimately found innocent? Why or why not? Drag each label to the correct location on the chart.Match each map with the correct year. The best way to locate a suffix is to look for a word partthat? Help me please.. On the first day in each month, Enid deposited $4 into her bank account and Jim deposited $3 into his. They opened these accounts on May 15, 1990. On December 31, 1990, they each had $72 dollars in their account. How much did each person deposit on May 15? compare between the contributions of kailash satyarthi and Martin lurcher King in building the society up Answer the following questions about divergent boundaries, such as the Mid-Atlantic Ridge, and their associated lavas: a. Divergent boundaries are characterized by outpourings of what type of lava: andesitic, basaltic lava, or rhyolitic? b. What is the source of these lavas? c. What causes the source rocks to melt? You are conducting a hypothesis where the null reads H0: 10 You have Just concluded that you should fail to reject the null hypothesis because Z* 1.49 and Zc 1.645 Select the best conclusion statement. A. There is overwhelming evidence that the mean is not 10. B. There is not overwhelming evidence that the mean is different than 10. C. Because the calculated value of Z was larger than the Zc, I rejected the null hypothesis D. Because the Z* was only a little bigger than the Zc, the test supports the null hypothesis and we conclude u-10 Find the coefficient of third term of (2x1)^6. Please answer this question now (05.05 MC) Exposing human subjects to experimental manipulations such as high levels of toxins is unethical. We often use model organisms for this reason. What attributes would you look for in selecting a good model organism for investigating the impact of toxins in humans? A good model organism should be able to be easily maintain in the laboratory, be fast growing, with a fast generation time and be as closely related to humans as possible. Cost is the only consideration in selecting a model organism, since all living things are made of cells anything found will apply to humans. The best choice will must be the very closely related to humans, such as chimps, since anything found in other species will not apply to humans. The most important consideration in selecting a model organism is how the public will feel about doing experiments on that species, so the best choice would generally be a very simple organism like bacteria that people don't care very much about. Select the correct answer. Which of Dee's actions in "Everyday Use" by Alice Walker is in line with the following description of her character? She was determined to stare down any disaster in her efforts. Her eyelids would not flicker for minutes at a time. Often I fought off the temptation to shake her. At sixteen she had a style of her own: and knew what style was. A. changing her name B. taking pictures of Maggie C. eating chitlins and collards D. marrying Hakim-a-barber E. giving the quilts to Maggie Choose the word whose stress is placed differently from that of the others.A. repair B. invite C. because D. cooking find the interest rate r when p = 800, a = 2700, and t = 3. A man borrows $200 000 to buy a sports car. He is charged a simple interest of2.88% per annum. If the loan is for 7 years, find the(a) interest payable(b) amount of each repayment if the total sum is to repaid in 84 equalinstallments. Help me please thank yall What makes Bernice Bobs Her Hair a modernist story? Select all that apply. It focuses on the concept of individual identity. It emphasizes the changing values of the time. It discusses the effects of war on modern society. It portrays a sense of disillusionment with the world. It explores the conflict of civilization and nature.