Please help if you can

Answer:

D

Step-by-step explanation:

since sam invest the least, let a be the amount invested by sam

sam = a

paul = a + 5000

bob = a + 5000 + 4000

3a + 14000 = 50000

3a = 36000

a = 12000

thus sam is 12000, paul is 17000 and Bob is 21000

therefore the ratio of B:P:S is 21:17:12

profit by paula is 17/50 x 70000 = 23800

The profit by Paula is 17/50 x 70000 = 23800.

We have given that Bob, Paula and Sam invest $50000 in a business. Bob invests $4000 more than Paul does and Paul invests $5000 more than Sam does. If the total profit was $70000

Since sam invest the least, let a be the amount invested by sam

Therefore we get,

sam = a

The investment of Paul = a + 5000

Bob = a + 5000 + 4000

3a + 14000 = 50000

3a = 36000

divide both sides by 3 so we get,

a=36000/3

a = 12000

Therefore, sam is 12000,

paul =5000+12000=17000 and

Bob =12000+9000= 21000

Therefore the ratio of B:P:S is 21:17:12

The profit by Paula is 17/50 x 70000 = 23800.

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Answer:

D. Observational Study

Explanation:

An observational  study is one in which all the participants are subjected to a common treatment and then compared to people who did not receive the same treatment. This is the case with the students who where subjected to the same treatment; an additional rehearsal session. They are then observed by the professor and compared to those who did not participate in the experiment.  

This is also an example of a cohort observational study. A cohort observational study is one in which all the participants have a common uniting factor. They are made to undergo a treatment and then compared to those who did not receive the treatment. This type of study  is subject to bias because a positive or negative result might be because of other factors not related to the study.

Answer:

A. 1/2

Step-by-step explanation:

20x=10

Divide 20 on both sides of the equation to get x by itself

20x=10

___.  __

20.     20

x =1/2

Answer:

A) x= 1/2

Step-by-step explanation:

20x= 10 we then divide 10 by 20 to get x= 10/20 or if we simplify x= 1/2. Thus answer choice A) is correct!

Answer:

a) profit = (new account opened x 5000) -3500

b) Opening account is binomial distribution with n =25 and p = 0.01

c) Probability of loss is 0.77781 --I don't recommend the company that it running the seminar

d) n ≅ 71

Step-by-step explanation:

See attached image

Answer:

[tex]t=\frac{(43.5 -40.1)-(0)}{3.678\sqrt{\frac{1}{20}+\frac{1}{20}}}=2.923[/tex]

The degrees of freedom are

[tex]df=20+20-2=38[/tex]

And the p value is given by:

[tex]p_v =2*P(t_{38}>2.923) =0.0058[/tex]

Since the p value for this cae is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true means for this case are significantly different

Step-by-step explanation:

When we have two independent samples from two normal distributions with equal variances we are assuming that  

[tex]\sigma^2_1 =\sigma^2_2 =\sigma^2[/tex]

And the statistic is given by this formula:

[tex]t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2}}}[/tex]

Where t follows a t distribution with [tex]n_1+n_2 -2[/tex] degrees of freedom and the pooled variance [tex]S^2_p[/tex] is given by this formula:

[tex]S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}[/tex]

The system of hypothesis on this case are:

Null hypothesis: [tex]\mu_1 = \mu_2[/tex]

Alternative hypothesis: [tex]\mu_1 \neq \mu_2[/tex]

We have the following data given:

[tex]n_1 =20[/tex] represent the sample size for group 1

[tex]n_2 =20[/tex] represent the sample size for group 2

[tex]\bar X_1 =43.5[/tex] represent the sample mean for the group 1

[tex]\bar X_2 =40.1[/tex] represent the sample mean for the group 2

[tex]s_1=4.1[/tex] represent the sample standard deviation for group 1

[tex]s_2=3.2[/tex] represent the sample standard deviation for group 2

First we can begin finding the pooled variance:

[tex]\S^2_p =\frac{(20-1)(4.1)^2 +(20 -1)(3.2)^2}{20 +20 -2}=13.525[/tex]

And the deviation would be just the square root of the variance:

[tex]S_p=3.678[/tex]

The statistic is givne by:

[tex]t=\frac{(43.5 -40.1)-(0)}{3.678\sqrt{\frac{1}{20}+\frac{1}{20}}}=2.923[/tex]

The degrees of freedom are

[tex]df=20+20-2=38[/tex]

And the p value is given by:

[tex]p_v =2*P(t_{38}>2.923) =0.0058[/tex]

Since the p value for this cae is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true means for this case are significantly different

Using the t-distribution, as we have the standard deviation for the sample, it is found that the researcher can conclude that there is a difference between the population means at the 0.05 significance level.

At the null hypothesis, it is tested if there is no difference, that is:

[tex]H_0: \mu_1 - \mu_2 = 0[/tex]

At the alternative hypothesis, it is tested if there is a difference, that is:

[tex]H_a: \mu_1 - \mu_2 \neq 0[/tex]

For each sample, we have that they are given by

[tex]\mu_1 = 43.5, s_1 = \frac{4.1}{\sqrt{20}} = 0.9168[/tex]

[tex]\mu_2 = 40.2, s_2 = \frac{3.2}{\sqrt{20}} = 0.7155[/tex]

Hence, for the distribution of differences, the mean and the standard error are given by:

[tex]\overline{x} = \mu_1 - \mu_2 = 43.5 - 40.2 = 3.3[/tex]

[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{0.9168^2 + 0.7155^2} = 1.163[/tex]

It is given by:

[tex]t = \frac{\overline{x} - \mu}{s}[/tex]

In which [tex]\mu = 0[/tex] is the value tested at the null hypothesis, hence:

[tex]t = \frac{\overline{x} - \mu}{s}[/tex]

[tex]t = \frac{3.3 - 0}{1.163}[/tex]

[tex]t = 2.84[/tex]

Considering a two-tailed test, as we are testing if the mean is different of a value, with a significance level of 0.05 and 20 + 20 - 2 = 38 df, the critical value is of [tex]|z^{\ast}| = 2.0244[/tex].

Since the absolute value of the test statistic is greater than the critical value, it is found that the researcher can conclude that there is a difference between the population means at the 0.05 significance level.

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Answer:

Inverse of f(x)

               [tex]f^{l} (x) = \frac{8 x}{3-x}[/tex]

Step-by-step explanation:

Explanation:-

Step(i):-

Given the function

                        [tex]f(x) = \frac{3 x}{8+x}[/tex]

Given function is one-one and onto function

Hence f(x) is bijection function

                   [tex]y = f(x) = \frac{3 x}{8+x}[/tex]

now cross multiplication, we get

            ( 8+x)y = 3 x

             8 y + x y = 3 x

             8 y = 3 x - x y

taking Common 'x' we get

            x (3 - y) = 8 y

                   [tex]x = \frac{8 y}{3-y}[/tex]

Step(ii):-

The inverse function

                 [tex]x = \frac{8 y}{3-y} = f^{l}(y)[/tex]

The inverse function of x

                  [tex]f^{l}(x) = \frac{8 x}{3-x}[/tex]

Final answer:-

Inverse of f(x)

               [tex]f^{l} (x) = \frac{8 x}{3-x}[/tex]

Answer:

[tex]45\pi$ square inches[/tex]

Step-by-step explanation:

The radius, r of the expanding circle of oil is modeled by the function:

[tex]r=3\sqrt{s}[/tex] , where s is time in seconds.

When s=5

Radius [tex]r(5)=3\sqrt{5}$ inches[/tex]

Area of a circle [tex]=\pi r^2[/tex]

Therefore, the area of the oil spill when s=5 seconds

[tex]=\pi* (3\sqrt{5})^2\\=45\pi$ square inches[/tex]

The area of the spill when s=5 seconds is 45pi square inches.

Answer:

300

Step-by-step explanation:

5x60=5x6 tens it equal to 30 tens. 30 tens equals 300

Answer:

see below

Step-by-step explanation:

there are 6 tens in 60!

5x60 = 5 x 6 tens

= 30 tens

= 300

Answer:

21

Step-by-step explanation:

Answer:

6.7

Step-by-step explanation:

Answer:

The answer is 0.31

Step-by-step explanation:

Old Method                                       New Method                          .

Mean                      73.5625                  Mean            75.70588

Standard Error        3.143736             Standard Error  2.923994

Median                    72                          Median            75

Mode                       90                          Mode               64

Standard deviation  12.57494           Standard deviation 12.05594

Sample Variance     158.1292            Sample Variance     145.3456

Kurtosis                     -1.14544              Kurtosis                   -0.76646

Skewness                 0.171025             Skewness                0.091008

Range                       39                        Range                      41

Minimum                   55                        Minimum                 56

Maximum                  94                        Maximum                 97

Sum                          1177                        Sum                        1287

Count                         16                         Count                      17

State the hypotheses. The first step is to state the null hypothesis and an alternative hypothesis.

Null hypothesis: μNew< μOld

Alternative hypothesis: μNew > μOld

Note that these hypotheses constitute a one-tailed test. The null hypothesis will be rejected if the mean difference between sample means is too small.

Formulate an analysis plan. For this analysis, the significance level is 0.05. Using sample data, we will conduct a two-sample t-test of the null hypothesis.

Analyze sample data. Using sample data, we compute the standard error (SE), degrees of freedom (DF), and the t statistic test statistic (t).

[tex]SE=\sqrt{\frac{S_1^2}{n_1} +\frac{S_2^2}{n_2} } \\\\SE=4.29[/tex]

DF = 31

[tex]t = \frac{(x_1-x_2)-d}{SE} \\\\t = - 0.4997[/tex]

where s1 is the standard deviation of sample 1, s2 is the standard deviation of sample 2, n1 is the size of sample 1, n2 is the size of sample 2, x1 is the mean of sample 1, x2 is the mean of sample 2, d is the hypothesized difference between population means, and SE is the standard error.

The observed difference in sample means produced a t statistic of - 0.499. We use the t Distribution Calculator to find P(t < - 0.499) = 0.311

Therefore, the P-value in this analysis is 0.311.

Interpret results. Since the P-value (0.311) is greater than the significance level (0.05), we cannot reject the null hypothesis.

From the above test we do have sufficient evidence in the favor of the claim that new method is efficient than the old method.

Answer:

The 95% confidence interval estimate for the population mean life of compact fluorescent light bulbs in this shipment is between 7,255 hours and 7,745 hours.

Step-by-step explanation:

We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1-0.95}{2} = 0.025[/tex]

Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].

So it is z with a pvalue of [tex]1-0.025 = 0.975[/tex], so [tex]z = 1.95[/tex]

Now, find the margin of error M as such

[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]

In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.

[tex]M = 1.96*\frac{1000}{\sqrt{64}} = 245[/tex]

The lower end of the interval is the sample mean subtracted by M. So it is 7500 - 245 = 7255 hours.

The upper end of the interval is the sample mean added to M. So it is 7500 + 245 = 7745 hours.

The 95% confidence interval estimate for the population mean life of compact fluorescent light bulbs in this shipment is between 7,255 hours and 7,745 hours.

A means of the estimate numerical, the variation in that estimate is referred to as the confidence interval, therefore its value is "[tex][7255, 7745][/tex]".

[tex]95\%[/tex] C.I. for a mean lifetime is given by

[tex]= [ \overline{X} - \tau_{0.975} \frac{\sigma}{\sqrt{n}} , \overline{X} + \tau_{0.975} \frac{\sigma}{\sqrt{n}} ][/tex], where

[tex]\bar{X}[/tex] (sample mean) [tex]= 7500[/tex]

[tex]\sigma[/tex] (standard deviation)[tex]= 1000[/tex]

[tex]n = 64[/tex]

by putting the value into the above-given formula we get the value that is  [tex]= [7255, 7745].[/tex]

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Answer:

4.24

Step-by-step explanation:

To solve this, use the Pythagorean therom. A^2 + b^2 = C^2

in this case a = 3  and b = 3

so 9 + 9 =  sqrt 18  

4.24

Answer:3√(2)

Step-by-step explanation:

DF=3

EF=3

DE=√(3^2 + 3^2)

DE=√(3x3 + 3x3)

DE=√(9+9)

DE=√(18)

DE=√(2 x 9)

DE=√(2) x √(9)

DE=√(2) x 3

DE=3√(2)

Answer:

subtraction

Step-by-step explanation:

In order to find out how many more flowers you need, you need to subtract both of the numbers to get the difference.

Answer:19

Step-by-step explanation:subtract 27 from 8.

Answer: an option is 2736

and we only have two possible solutions, the other is 6732

Step-by-step explanation:

we want to write a number:

a73b, where a and b are one digit numbers (0 to 9) in such way that the number is divisible by 36.

Now, we know that 36 is multiple of 6, so 6*6 = 36

The multiples of 36 are always even numbers, so we can discard all the odd options for b.

We also can discard the option a = 0, because we want a 4 digit number.

now, let's do it by brute force.

if a = 1, we have:

173b, now you can give b different values (only even values) and see if some of them is divisible by 36. You will find that none is.

if a = 2

273b

when b = 6, we have:

N = 2736, that is divisible by 36 as:

2736/36 = 79, so this is a multiple of 36.

now, you can keep changing the value of a and find all the different possible solutions.

if a = 3,

373b is not divisible by 36 for any value of b

if a = 4

473b  is not divisible by 36 for any value of b

if a = 5

573b  is not divisible by 36 for any value of b

if a= 6

673b  it is divisible by 36 when b = 2.

6732/36 = 187

if a = 7

773b  is not divisible by 36 for any value of b

if a = 8

873b  is not divisible by 36 for any value of b

if a = 9

973b  is not divisible by 36 for any value of b

So we only have two possible solutions

The different solutions this problem have are 2736 and 6732.

This is a part of a number which consists of numerals from 0 to 9.

a73b is the first number where a and b are one digit numbers (0 to 9) which is divisible by 36.

All multiples of 36 are always even numbers, so odd number options for b isn't considered.

If a = 2 when b = 6, we have:  it is divisible by 36 when b = 2.

N = 2736, which is divisible by 36 to give 76 hence it is a multiple of 36.

673b is divisible by 36 when b = 2.

N = 6732 which is divisible by 36 to give 187 hence it is a multiple of 36.

Hence, the two values are  2736 and 6732.

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Answer:

2 divided

Step-by-step explanation:

Answer:

Step-by-step explanation:

A general equation of a hyperbola is

 x^2     y^2

-------- - ------- = 1   (This applies only when the center of the hyperbola

 a^2     b^2                               is at (0, 0)  ).

You must compare the given equations to this standard form to identify which represents the hyperbola shown, and also you must share the illustration of the hyperbola.

The equation represents the hyperbola shown in the graph is  (y - 1)² / 9 - (x + 4)² / 4  = 1

A hyperbola is a type of smooth curve lying in a plane, defined by its geometric properties or by equations for which it is the solution set.

A hyperbola has two pieces, called connected components or branches, that are mirror images of each other and resemble two infinite bows.

Given that, a graph, showing hyperbola, we need to find the equation,

We have the general equation for up - down facing hyperbola as

(y - k)² / b²- (x - h)² / a²  = 1.

Let's start listing the properties of this graph -

Taking a look at the graph we see that the center point of our hyperbola here is (- 4, 1).

Therefore, (h, k) = (- 4,1).

This is the semi distance from the center to one of the vertices. Here it will be the distance from points (- 4,1) and (- 4,4) or 3 unit difference.

Therefore, a = 3.

That gives asymptotes. Now remember that it will be in the form

y = ± b / a.

We already know a = 3, so we have to find b.

Looking at this graph we can say that another point besides (- 4,1) that lies on the "dotted line" is (- 2, - 2).

Calculating the slope of the dotted line would be as follows,

Given: (- 4,1) and (- 2, - 2)

Slope = - 2 + 4 / - 2 - 1 = 2 / 3

We have the equation y = 2 / 3x.

Therefore, b = 2.

Let's substitute to equation...

h = - 4, k = 1, b = 2, a = 3

(y - 1)² / (3)²- (x + 4)² / (2)²  = 1

(y - 1)² / 9 - (x + 4)² / 4  = 1

Hence, the equation represents the hyperbola shown in the graph is  (y - 1)² / 9 - (x + 4)² / 4  = 1

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The complete question is attached

Answer:12 months

Step-by-step explanation:

400+400=800 so  950-800=150 1800/150=12

Answer:

mean: 46.63636

median: 34

mode: 87

range:95

How To:

Step 1 : To find Mean

    Average = ( 1 + 5 + 5 + 7 + 8 + 10 ) / 6

             =36 / 6

    Mean = 6

Step 2 : To find Median

   Middle value = ( 5 + 7 ) / 2

               = 12 / 2

    Median = 6

Step 3 : To find Mode

   Mode = 5 (The number with more repetition, here 5 is repeated two times)

Step 4 : To find Range

    Range = Largest number - Smallest number

       = 10-1

       = 9

Range = 9

Answer:

Mean: 46.6

Mode: 87

Median: 34

Range: 95

Step-by-step explanation:

Mean: (finding the average)

Median: (the middle number of the data set)

Mode: (the most number repeated from the data set)

Range: (is the difference between the highest value and the lowest value)

first arrange the following data set.

23, 87, 19, 34, 37, 87, 81, 5, 14, 100, 26

so:

5, 14, 19, 23, 26, 34, 37, 81, 87, 87, 100

Lets us first find the mean by adding up all the numbers and dividing it by the amount of numbers in the data set.

Mean: 5 + 14 + 19 + 23 + 26 + 34 + 37 + 81 + 87 + 87 + 100 = 513/11 = 46.6

Mode: 87

Median: 34

Range: 100 - 5 = 95

Answer:

20x + 30y = 680

Step-by-step explanation:

Give me a good rating please!

An equation is a mathematical statement that is made up of two expressions connected by an equal sign.

The equation represents the number of $20 and $30 gift cards bought.

20x + 30y = 680

An equation is a mathematical statement that is made up of two expressions connected by an equal sign.

We have,

Number of gift cards for $20 = x

Number of gift cards for $30 = y

Total amount spend on gift card = $680

The equation represents the number of $20 and $30 gift cards bought.

20x + 30y = 680

Thus,

The equation represents the number of $20 and $30 gift cards bought.

20x + 30y = 680

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Answer:

For 0 correct answer [tex]^4c_0p^0q^{4-0}[/tex]

For 1 correct answer [tex]^4c_1p^1q^{4-1}[/tex]

For 2 correct answer [tex]^4c_2p^0q^{4-2}[/tex]

For 3 correct answer [tex]^4c_3p^1q^{4-3}[/tex]

For 4 correct answer [tex]^4c_4p^1q^{4-4}[/tex]

Step-by-step explanation:

It is given that there are 4 questions n = 4

Number of choices is 4

So probability of getting correct answer [tex]=\frac{1}{4}[/tex]

Probability of getting incorrect answer [tex]=1-\frac{1}{4}=\frac{3}{4}[/tex]

Probability distribution is given by [tex]^nc_rp^rq^{n-r}[/tex]

Therefore probability distribution of 0 correct answer

[tex]^4c_0p^0q^{4-0}[/tex]

Therefore probability distribution of 1 correct answer

[tex]^4c_1p^1q^{4-1}[/tex]

Therefore probability distribution of 2 correct answer

[tex]^4c_2p^0q^{4-2}[/tex]

Therefore probability distribution of 3 correct answer.

[tex]^4c_3p^1q^{4-3}[/tex]

Therefore probability distribution of 4 correct answer.

[tex]^4c_4p^1q^{4-4}[/tex]

Answer:

18.333

Step-by-step explanation:

Answer:

14a8y3 - 7 Ay5 + 28a12y2-  7ay2 • (4a11 + 2a7y - y3)

Step-by-step explanation:

Equation at the end of step  1  :

 (((14•(a8))•(y3))-(7a•(y5)))+((22•7a12)•y2)

Step  2  :

Equation at the end of step  2  :

 (((14•(a8))•(y3))-7ay5)+(22•7a12y2)

Step  3  :

Equation at the end of step  3  :

 (((2•7a8) • y3) -  7ay5) +  (22•7a12y2)

Pull out like factors

Answer:   7ay2 • (4a11 + 2a7y - y3)

Hope this helps.

Answer:I believe it would be 5/12

Step-by-step explanation:

You add all of them up then since it's 5 grapes and in total there is 12 fruit snacks. It should be 5 grapes of 12 fruit snacks in the bag.

Answer:

3 1/4

Step-by-step explanation:

3/4 + (1/3 ÷1/6) - (-1/2)

Subtracting a negative is adding

3/4 + (1/3 ÷1/6) +1/2

Parentheses first

Copy dot flip

3/4 + (1/3 * 6/1) +1/2

3/4 + 2 + 1/2

Get a common denominator

3/4 + 2 + 2/4

2 + 5/4

2 + 4/4 +1/4

2+1 + 1/4

3 1/4

Answer:

The height of the building: g

Distance from the building to the base of the ladder: 57

The length of the ladder: m

Angle the ladder makes with the building: k

Angle the ladder makes with the ground: 55

Step-by-step explanation:

Based off the location of the variables and numbers, the descriptions match where they are.

Hope that helps!

Answer:

The absurdity of Harrison's exaggerated handicaps ridicules society's obsession with equality.Step-by-step explanation:

Answer:

Step-by-step explanation:

In the year 2081, the 211th, 212th, and 213th amendments to the Constitution dictate that all Americans are fully equal and not allowed to be smarter, better-looking, or more physically able than anyone else. The Handicapper General's agents enforce the equality laws, forcing citizens to wear "handicaps": masks for those who are too beautiful, loud radios that disrupt thoughts inside the ears of intelligent people, and heavy weights for the strong or athletic.

One April, 14-year-old Harrison Bergeron, an intelligent, athletic, and good-looking teenager, is taken away from his parents, George and Hazel Bergeron, by the government. They are barely aware of the tragedy, as Hazel has "average" intelligence (a euphemism for stupidity), and George has a handicap radio installed by the government to regulate his above-average intelligence.

Hazel and George watch ballet on television.They comment on the dancers, who are weighed down to counteract their gracefulness and masked to hide their attractiveness. George's thoughts are continually interrupted by the different noises emitted by his handicap radio, which piques Hazel's curiosity and imagination regarding handicaps. Noticing his exhaustion, Hazel urges George to lie down and rest his "handicap bag", 47 pounds (21 kg) of weights locked around George's neck. She suggests taking a few of the weights out of the bag, but George resists, aware of the illegality of such an action.

On television, a news reporter struggles to read the bulletin and hands it to the ballerina wearing the most grotesque mask and heaviest weights. She begins reading in her unacceptably natural, beautiful voice, then apologizes before switching to a more unpleasant voice. Harrison's escape from prison is announced, and a full-body photograph of Harrison is shown, indicating that he is seven feet (2.1 m) tall and burdened by three hundred pounds (140 kg) of handicaps.

George recognizes his son for a moment, before having the thought eliminated by his radio. Harrison himself then storms the television studio in an attempt to overthrow the government. He calls himself the Emperor and rips off all of his handicaps, along with the handicaps of a ballerina, whom he proclaims his "Empress". He orders the musicians to play, promising them nobility if they do their best. Unhappy with their initial attempt, Harrison takes control for a short while, and the music improves. After listening and being moved by the music, Harrison and his Empress dance while flying to the ceiling, then pause in mid-air to kiss.

Diana Moon Glampers, the Handicapper General, enters the studio and kills Harrison and the Empress with a ten-gauge double-barreled shotgun. She forces the musicians to put on their handicaps, and the television goes dark. George, unaware of the televised incident, returns from the kitchen and asks Hazel why she was crying, to which she replies that something sad happened on television that she cannot remember. He comforts her and they return to their average lives.