is housework hazardous to your health? a study in public health report compares the life expectancies of 25-year-old white women in the labor force with those who are housewives. how large a sample would have to be taken from each group in order for you to be 95% con dent that the estimate of the difference in mean life expectancies for the two group is within 1 year of the true difference? assume that equal sample sizes will be selected from the two groups and that the standard deviation for both groups is approximately 15 years.

Answers

Answer 1

the difference in mean life expectancies for the two groups is within 1 year of the true difference is 1729

Health issues can arise from substances other than chemicals like bleach. The way you clean your house and the environment in which you live both matters. Scientists caution that performing these tasks could have a detrimental effect on your health.

A Z-score is a metric that quantifies how closely a value relates to the mean of a set of values. Standard deviations from the mean are used to measure Z-score.

Given data:

σ₁ = σ₂ = 15

n₁ = n₂ = n

Margin of error = 1

Confidence level = 95% = α = 1 - 0.95 = 0.05

z score of α / 2 = 0.05 / 2 = 1.96 , n₁ = n₂ = ?

For the difference of mean test, the margin of error will be:

E = z score  α / 2 [tex]\sqrt \frac{(SD1)^{2} }{n1}+\sqrt \frac{(SD2)^{2} }{n2}[/tex]

[tex]1 = 1.96 \sqrt\frac{(15)^{2} }{n} + \sqrt \frac{(15)^{2} }{n}[/tex]   [∵ n₁ = n₂ = n]

[tex]1 = 1.96 * 15 \sqrt \frac{2}{n}[/tex]

1 = 41.58 / √n

√n = 41.58 / 1 = 41.58

On squaring both sides:

n = 1728.90 ≈ 1729

∴ n₁ = n₂ = 1729

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Related Questions

Question 3 (5 points) Convert the decimal 0.929292... to a fraction.

Answers

Answer:

92 over 100

Step-by-step explanation:

A number you can square to give an answer bigger than 500 but bigger than 600

Answers

The number that you can square to give an answer bigger than 500 but bigger than 600 = 25.

What is the square of a number?

The square of a number is defined as the ability to multiple the given number by itself to give a perfect whole number.

For example the square of 2, which is written as 2² = 2×2 = 4

From the given scenario, the number that would be squared to give an answer bigger than 500 but bigger than 600 = 25

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100 brainly!!! Which of the following functions is graphed below?

Answers

Answer: the answer is B

7
1
-5
35
-4 24
-3 15
-2 8
-1 3
0 0
1 -1
Match the average rates of change of f(x) to the corresponding intervals.
-7
-4
300
[-5, -1]
(-4,-1]
[-3, 1]
-2,1]

Answers

The rates of changes of the given function for the corresponding intervals are:  [-5, -1] = -8, [-4, -1] = -7, [-3, -1] = -6, [-2, -1] = -5.

What is function?

A function, according to a technical definition, is a relationship between a set of inputs and a set of potential outputs, where each input is connected to precisely one output.

This means that a function f will map an object x to exactly one object f(x) in the set of potential outputs if the object x is in the set of inputs (referred to as the domain) (called the codomain).

The rate of change of a function can be calculate using the formula:

[tex]R = \frac{f(x_2)-f(x_1)}{x_2-x_1}[/tex]

Putting the value from the question:

given [x₁, x₂] = [-5, -1]

f(-5) = 35 , f(-1) = 3

Putting these value in formula:

[tex]R = \frac{3-35}{-1 -(-5)}[/tex]

R = -32/4

R = -8

given [x₁, x₂] = [-4, -1]

f(-4) = 24, f(-1) = 3

Putting these value in formula:

[tex]R = \frac{3-24}{-1 -(-4)}[/tex]

R = -21/3

R = -7

given [x₁, x₂] = [-3, -1]

f(-3) = 15, f(-1) = 3

Putting these value in formula:

[tex]R = \frac{3-15}{-1 -(-3)}[/tex]

R = -12/2

R = -6

given [x₁, x₂] = [-2, -1]

f(-2) = 8, f(-1) = 3

Putting these value in formula:

[tex]R = \frac{3-8}{-1 -(-2)}[/tex]

R = -5/1

R = -5

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railroad accidents a researcher wishes to study railroad accidents. he wishes to select 4 railroads from 15 class i railroads, 2 railroads from 8 class ii railroads, and 1 railroad from 7 class iii railroads. how many different possibilities are there for his study?

Answers

Different possibilities for the given case are, 267540

4 railroads chosen from 15 class I railroads

2 railroads chosen from 8 class II railroads

1 railroad chosen from 7 class III railroads

So total combinations    = ¹⁵C₄ ˣ ⁸C₂ ˣ ⁷C₁

   = (15!)/(4!*11!) x (8!)/(2!6!) x (7!)/(1!6!)

   = 15 x 7 x 13 x 4 x 7 x 7 = 267540

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In the Mediterranean, the Mycenaeans rose to prominence by a mix of military prowess, economic connections, and cultural sway.

Thus, Military Might: The Mycenaeans had a strong military force and were expert warriors. They used sophisticated bronze weapons and chariot warfare as a tactic.

They were able to increase their influence and take control of neighbouring territories thanks to their military might.

Control over Trade Routes: The Mycenaeans had complete control over key trade routes in the Mediterranean, particularly those that extended from the Aegean to the eastern Mediterranean and beyond.

Thus, In the Mediterranean, the Mycenaeans rose to prominence by a mix of military prowess, economic connections, and cultural sway.

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The angles of a triangle are in the ratio 2:8:5 find the size of each side

Answers

Answer:

24° , 60° , 96°

Step-by-step explanation:

sum the parts of the ratio, 2 + 8 + 5 = 15 parts

divide the sum of the angles in a triangle by 15 to find the value of one part of the ratio.

180° ÷ 15 = 12° , then

2 parts = 2 × 12° = 24°

5 parts = 5 × 12° = 60°

8 parts = 8 × 12° = 96°

the 3 angles in the triangle are 24° , 60° , 96°

HELP ASAP PLSSSPLSPSLSPLSSSSSS
Graph g(x) = |x + 3|.

Answers

Answer:

Hope this helps!!

What is the value of x, y, and z??

Answers

The values x = 0, y = 0.03 and z = 0.039 for the three events A,B and C with their associated probabilities.

Axioms of probability

The following are axioms of probability for the purpose of answering the given question:

Two events are said to be mutually exclusive if the probability of their intersection is zero.

Two events are said to be independent if the probability of their intersection is equal to the product of their respective probability

From the question, the probability of the event A alone occurring=0.10

the probability of the event B alone occurring=0.30

the probability of the event C alone occurring=0.39

Given that B and C are mutually exclusive events;

x = probability of the intersection of B and C=0

A and C are said to be independent so; z = probability of the intersection of A and C = 0.10×0.39

probability of the intersection of A and C = 0.039

If A and B are not mutually exclusive events and are independent then;

y = probability of the intersection of A and B

probability of the intersection of A and B = 0.10×0.30

probability of the intersection of A and B = 0.03.

Hence, the values of x,y and z are 0, 0.03 and 0.039 respectively for the events A,B and C with their associated probabilities.

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according to government data, 51% of employed women have never been married. rounding to 4 decimal places, if 15 employed women are randomly selected: a. what is the probability that exactly 2 of them have never been married? b. that at most 2 of them have never been married? c. that at least 13 of them have been married?

Answers

a) The probability that exactly 2 of them have never been married is[tex]0.0026 \text{ or }2.6*10^{-3}[/tex]

b) The probability that at most 2 of them have never been married is[tex]0.0029\text{ or }2.9*10^{-3}[/tex]

c) The probability that at least 13 of them have been married is [tex]0.0046 \text{ or } 4.6*10^{-3}[/tex]

a)  What is the probability that exactly 2 of them have never been married?

By applying binomial probability distribution method,

[tex]P(x)=^{n}C_{x}p^{x}q^{n-x}[/tex]

Substitute,

P(x) =Binomial probability =  51% = 0.51

x = No. of times of an outcome = 2

n = No. of trials = 15

q =  Probability of failure = 49% = 0.49

[tex]^{n}C_{x}[/tex] = No. of combinations

[tex]P(2)=^{15}C_{2}*(0.51)^{2}*(0.49)^{15-2}\\\\P(2)=\frac{15!}{13!2!} *(0.51)^{2}*(0.49)^{13}\\\\P(2)=0.0026 \text{ or }2.6*10^{-3}[/tex]

b) What is the probability that at most 2 of them have never been married?

By applying binomial probability distribution method,

[tex]P(x)=^{n}C_{x}p^{x}q^{n-x}[/tex]

Substitute,

P(x) =Binomial probability =  51% = 0.51

x = No. of times of an outcome = 0,1,2

n = No. of trials = 15

q =  Probability of failure = 49% = 0.49

[tex]^{n}C_{x}[/tex] = No. of combinations

[tex]P(0-2)=^{15}C_{0}*(0.51)^{0}*(0.49)^{15-0}+^{15}C_{1}*(0.51)^{1}*(0.49)^{15-1}+^{15}C_{2}*(0.51)^{2}*(0.49)^{15-2}\\\\P(0-2) = 2.253*10^{-5}+15*0.51*4.59987*10^{-5}+2.563*10^{-3}\\\\P(0-2)=0.0029 \text{ or }2.9*10^{-3}[/tex]

c)What is the probability that at  least 13 of them have been married?

By applying binomial probability distribution method,

[tex]P(x)=^{n}C_{x}p^{x}q^{n-x}[/tex]

Substitute,

P(x) =Binomial probability =  51% = 0.51

x = No. of times of an outcome = 13,14,15

n = No. of trials = 15

q =  Probability of failure = 49% = 0.49

[tex]^{n}C_{x}[/tex] = No. of combinations

[tex]P(13-15)=^{15}C_{13}*(0.51)^{13}*(0.49)^{15-13}+^{15}C_{14}*(0.51)^{14}*(0.49)^{15-14}+^{15}C_{15}*(0.51)^{15}*(0.49)^{15-15}\\\\P(13-15)= 105*(0.51)^{13}*(0.49)^{2}+15* (0.51)^{14}*(0.49)+(0.51)^{15}\\\\P(13-15)= 0.0046 \text{ or } 4.6*10^{-3}[/tex]

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Which relation is a function?

Answers

The first one because it passes the vertical line test

If y varies inversely as x, and y = 22 when x = 6, find x when y = 15.

Answers

Step-by-step explanation:

y varies INVERSELY as x.

that means

y = k/x

therefore,

22 = k/6

k = 22×6 = 132

and then, when y = 15

15 = 132/x

15x = 132

x = 132/15 = 8.8

If the interest earned on an account after 2 years is 15$ how much would it be after 10 years? why?

Answers

The amount of interest earned in 10 years is $75.

What is interest?Interest is the sum over and above the original amount (the amount borrowed) that is paid to a lender or depositor by a borrower or deposit-taking financial institution at a set rate. It is not the same as a fee that the borrower might pay to the lender or another entity.It also differs from a dividend, which is money given to shareholders (owners) by a company from its profit or reserve but not at a set rate predetermined in advance, but rather on a pro-rata basis as a share of the reward received by risk-taking business people when revenue is earned that exceeds all costs.

So, interest earned after 2 years = $15

interest earned in 1 year = 15/2 = $7.5 interest earned in 10 years = 10 × $7.5= $ 75

Therefore, the amount of interest earned in 10 years is $75.

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considering the function for what values of x is f constant Options: (negative infinity,10]never(10,15)[15, infinity)

Answers

So, as shown at the function

f(x) is constant at the middle interval (10 , 15)

at which f(x) = 2 and the digit 2 is constant

so, the answer is (10 , 15)

Write the equation of the line in the slope-intercept form which is parallel to
y = −2x +5 and passing through the point (1, −4)

Answers

The equation of the line that is parallel to the line y = −2x +5 and passing through the point (1, −4) is y = -2x - 2.

How to form an equation?

Determine the known quantities and designate the unknown quantity as a variable while trying to set up or construct a linear equation to fit a real-world application.

The slope of two parallel lines is always the same.

The slope y-intercept form of an equation is y = mx + c where m is the slope.

Given the parallel equation y = -2x + 5 by compare slope = -2

Therefore,the equation will become y = -2x + c

Substitute,(1,-4) into this

-4 = -2(1) + c ⇒ c = -2

So equation converts as y = -2x - 2.

Hence "The equation of the line that is parallel to the line y = −2x +5 and passing through the point (1, −4) is y = -2x - 2".

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The length of a rectangle is 5 feet more than the width. The perimeter of the rectangle is 58 feet. Find the length & width of the rectangle.

Answers

Answer:

Length: 17 ft. Width: 12 ft.

Step-by-step explanation:

x + 5 + x +5 + x + x = 58

4x + 10 = 58

4x = 48

x = 12

12 + 5 = 17

Hi, can you help me to solve this problem please!!!

Answers

The Solution:

Given the graph of f(x), we are required to determine whether the degree of the function is ODD or EVEN, and also to determine whether the function itself is ODD.

An odd function is defined as a function that has f(–x) = –f(x) for any value of x. The opposite input gives the opposite output.

From the given graph of f(x), the function f(x) is ODD.

The degree of the function f(x) is odd since the f(x) itself is odd.

slope for point (7,2) and (1,-1)

Answers

Answer:  The slope is [tex]\frac{1}{2}[/tex].

Step-by-step explanation:

[tex]Slope = \frac{y_{2}-y_{1} }{x_{2}-x_{1} } =\frac{-1-2}{1-7} =\frac{-3}{-6} =\frac{3}{6}=\frac{1}{2}[/tex]

Find the exact solution to the equation 42 equals 3 x squared, leaving your answer in square root form. Show your work.
State if your solution is rational or irrational. Explain.
Find the closest integer approximation to your solution and explain how you found it.

Answers

The solution is x = √ 14, it is irrational

The closest integer approximation to the solution is 4

How to determine the value

From the information given, we have that;

42 equals 3 x squared

This is represented as;

3x² = 42

Let's take the following steps to determine the value of x

Divide both sides by the coefficient of x²

x² = 42/3

x² = 14

Take the square root of both sides, we have;

x = √ 14

The solution is an irrational number

What is an irrational number?

An irrational number is described as a number that cannot be expressed in a fractional form.

They are real numbers that expressed as quotients

Examples of irrational numbers are;

√5, √7, √11, √13

Now, let's find the square root, we have

= 3. 74

Take '7' as 1 and add to the whole number 3, we get;

= 4 ; to the closest integer

Hence, the value is 4

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Which of the following is equivalent to 1-2x > 3(x - 2)?
01-2x > 3x - 7
01-2x > 3x - 6
01-2x > 3x - 2
01-2x > 3x - 5
POSSIBLE POINTS:

Answers

Answer: 01-2x > 3x - 6

Step-by-step explanation: distributive property

please help please pleaseeee

Answers

Answer: x=59

Step-by-step explanation:

360-296=(x-24)+29

         64=x+5

         59=x

What is 3g^2 + 2g^2 - 4g simplified?

Answers

consider

[tex]3g^2+2g^2-4g[/tex]

note that the letter g is common to all the numbers in the equation, so we take the lowest power of g and make a common factor, that is:

[tex]3g^2+2g^2-4g=g(3g+2g-4)^{}\text{ = g(5g - 4)}[/tex]

so the correct answer is

g(5g - 4)

Answer: 9g

Step-by-step explanation:

3g^2 + 2g^2 - 4g

you simplify the exponents first, because of P.E.M.D.A.S.:

9g + 4g - 4g combine like terms

Answer: 9g

suppose 52% of the students in a university are baseball players. if a sample of 436 students is selected, what is the probability that the sample proportion of baseball players will be greater than 45%? round your answer to four decimal places.

Answers

Probability of proportion will be greater than 3.18

What is meant by Probability of Proportion?

Probability of Proportion: Probability represents the chances of some event happening. It is theoretical. Proportion summarizes how frequently some event actually happened

Population Proportion, p=0.52

sample proportion p'=0.45

sample size be n =436

probability of proportion will be greater than 52%

[tex]p(p' > 0.45)=p(p'-p\sqrt{p(1-p)/n} )[/tex]

[tex]=-p(z > (0.45-0.52)/\sqrt{0.52((1-0.52)/436}[/tex]

=P(z>-3.18)

probability of proportion will be greater than 3.18

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Paige makes bracelets and sells them online for $15 and $20. She buys all of her supplies in bulk. The table shows her sales for the last 3 months. During the 3-month period represented by the table, she ordered supplies twice. Each time, she spent $292.58 on supplies.

Answers

Paige's profit for the three-month period given the information provided in the question is $569.84.

What is the profit?

Profit is the difference between total revenue and total cost. Revenue is the product of total units sold and the price per output.

Profit = revenue - cost

Revenue from selling the $15 bracelet = total bracelets sold for the 3 months x price of the bracelet

(8 + 11 + 22) x 15

41 x $15 = $615

Revenue from selling the $20 bracelet =  total bracelets sold for the 3 months x price of the bracelet

(7 + 6 + 14) x $20

27 x $20 = $540

Total revenue = $615 + $540 = $1,155

Total cost =  $292.58  x 2  = $585.16

Profit = $1,155 - $585.16 = $569.84

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haresh is writing a coordinate proof involving an isosceles triangle. haresh places his triangle on the coordinate plane such that the base of the triangle lies along the x-axis. what coordinates should he assign to this third vertex of the isoceles triangle?

Answers

The third vertex of the isosceles triangle is (a/2, b).

Let one vertex of the triangle lies on the base of the x-axis as 'a' which is written as (a,0)

Similarly, the other vertex of the triangle lies on the base of the y-axis as 'b' which is written as (0,b)

Let other vertex be at origin (0, 0)

An isosceles triangle is a triangle that has at least two sides of equal length.

Hence, the vertex of the triangle is (a/2, b).

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It takes Allie 456
minutes to drive to the store. From the store, it takes her 734
minutes to drive to the car wash. How many minutes does it take Allie to drive to the store and then to the car wash?

Answers

It takes 1190 minutes for Allie to drive to the store and then to the car wash.

According to the question,

We have the following information:

Time taken by Allie to drive to the store = 456 minutes

Time taken by Allie to drive to the car wash from the store = 734 minutes

Now, we have to find the total time in minutes. So, we will add the total time taken by Allie to drive to the store and then to the car wash.

(Note that the time asked in the question is in minutes. So, we do not need to change the units of given time.)

Now,

The total time taken by Allie to drive to the store and then to the car wash = Time taken by Allie to drive to the store + Time taken by Allie to drive to the car wash from the store

The total time taken by Allie to drive to the store and then to the car wash = (456 + 734) minutes

The total time taken by Allie to drive to the store and then to the car wash = 1190 minutes

Hence, the total time taken by Allie to drive to the store and then to the car wash is 1190 minutes.

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What is the answer? Pls

Answers

Answer:

70

Step-by-step explanation:

f(1)=6, f(n)=f(n-1)+4

n = 1 → a1 = 6 ← given value

n = 2 → a2 = 6+4 = 10

n = 3 → a3 = 6+4+4 = 14

n = 4 → a4 = 6+4+4+4 = 18

n = 17 → a4 = 6+(4 * 16) =

(its 4 times 16 because 16 is 17 - 1 or n - 1)

n = 17 → a4 = 6+(64) = 70

socraticorg

Tony B

The difference between 75% of a number and 20% of the same number is 378.4 what is 40% of that number?

Answers

Answer:

40% of the number is 275.2.

Step-by-step explanation:

I am going to call the number x.

75% of the number: 0.75x

20% of the same number: 0.2x

The difference between 75% of a number and 20% of the same number is 378.4:

This means that:

0.75x - 0.2x = 378.4

0.55x = 378.4

x = 378.4/0.55

x = 688

40% of the number:

0.4*688 = 275.2

40% of the number is 275.2.

A pole 5 feet tall is used to support guy wire for a tower, which runs from the tower to a metal stake in the ground. After placing the pole, Zoe measures the distance from the pole to the stake and from the pole to the tower, as shown in the diagram below. Find the length of the guy wire to the nearest foot

Answers

The length of the guy wire to the nearest foot is 42 feet.

How to find the length of the guy wire?

The pole 5 ft tall is used to support the guy wire for the tower, which runs from the tower to a metal stake in the ground.

The situations forms a right angle triangle.

Therefore, the length of the guy wire can be found as follows:

Using trigonometric ratios, we can find the angle the guy wire made with the ground.

tan ∅ = opposite / adjacent

tan ∅ = 5 / 15

∅ = tan ⁻¹ 1 / 3

∅ = 18.4349488057

∅ = 18.43°

Therefore, let's find the length of the guy wire using the angle.

cos 18.43° =  adjacent / hypotenuse

0.94871060813 = 40 / h

h = 40 / 0.94871060813

h = 42.162488395

Therefore,

length of the guy wire = 42 feet

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If you cut me in half, my end face will remain the same. Two of my faces are the same, one is curved. What am I?

Answers

Answer: The moon

Step-by-step explanation:

The cone is the solid form that represents "If you cut me in half, my end face will remain the same. Two of my faces are the same, one is curved."

What is the volume of a cone?

The volume of a cone is defined as the amount of space occupied by a cone in a three-dimensional plane.

∵ The volume of the cone (V )= 1/3πhr²

The number of faces of a regular cone is one, which we may partition vertically into two halves.

This means one base face and lateral face

Now, the number of faces in one half equals the number of faces in the original form.

This meets the conditions outlined in the question.

So, the cone is a solid form.

Thus, the cone is the solid form that represents "If you cut me in half, my end face will remain the same. Two of my faces are the same, one is curved."

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In this isosceles triangle,
AB-AC
4 cm is the bottom line
The perimeter of the triangle is 22 cm
Work out the length of AB.

Answers

Answer:

the length of AB is 9

Step-by-step explanation:

an isosceles triangle is a type of triangle i which two of its sides are equivalent(equal). let AB=AC=x

perimeter=22

                  perimeter=AB+AC+BC

                                22=x+x+4

                                 22-4=2x

                                      18/2=2x/2

                                           9=x

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copy and complete each problem /20 = 11/55 Let a represent the row number in this pattern. Write a rule that tells you the number of dots, d, in row n (Hint: Your rule should begin with "d=") Row 1 Row 2 Row 3 Row 4 Calculate the boiling point of a 0.33 m solution of a solute in benzene.(Kb = 2.53C /m). explain the ideas (natrual rights,role of the government) and the complaints set forth in the declaration of independence What it mean for the brightness of bulbs in parallel if the potential difference across each one is the same as the potential difference across the battery?A. Not enough infoB. All the sameC. Decrease for each oneD. Increase for each one Find the element that is oxidized and the one that is reduced KClO3 + 6 FeSO4 + 3 H2SO4 --> KCl + 3 Fe2(SO4)3 + 3 H2O Estimate the time it would take you to drive 278 miles at38 miles per hour. Round to the nearest hour question In photograph Admission to a state fair is $10, and each ride ticket costs $2.50. Write an en What techniques does a comic book artist use to create an eye catching piece? Which fraction is equivalent to3-3? - 1 27 1 1 27 What function makes the HIV virus unique? Brianna's teacher asks her if these two expressions 3x + 5 and 4x are equivalent.Brianna says the expressions are equivalent because the value of each expression is 20 when x = 5.Is Brianna correct synlainthink ASAP please If all planets were the same distance from the sun, which would have the largest gravitational force between itself and the sun? Why? for each of the following polynomial functions, write the equation of a different polynomial function that has the same key characteristic. explain your thinking. larry south is leasing property from jim west. larry south transfers the rights of his leasehold estate to joe north. the transaction occurred because of: Show that (3 * 8 * x) = 6 * 4 * x (1/2x+7/10)(3/4x1/5) help me out please and thank you What is output by following code?C=c+2