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4 years ago

What is the approximate surface area of the sphere 15yd?

1 answer:

7 0

The surface area of a sphere is equal to [4 x Pi x R^2]. In other words, four multiplied by 3.14 multiplied by the radius squared. If the radius of a sphere is 15 yards, the approximate surface area is [4 x 3.14 x (15x15)] = [12.5 x 225] = [2,812 yd^2]. The surface area of a sphere with radius 15 yd is approximately 2,800 yards.

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cos (x°) = sin (90 - x°) Using complete sentences, explain why an infinite number of x values that will prove the trigonometric

Setler79 [48]

Cosx= sin(90-x)
From the RHS,
sin(90-x)= sin90cosx-cos90sinx
Since sin90=1, cos90=0
sin90cosx-cos90sinx=cosx-0=cosx (proven)

6 0

3 years ago

Read 2 more answers

I need help with these questions For 21) A:y=x+4 B:y=2x C:2x+2 D:2/3x+1

gtnhenbr [62]

19.
Option (B) is the correct one.

Explanation:

The equation of line be is ,
y = 2x-4,

we have general equation give by,
y = mx +c

wherr m is the slope of the line and x and y are the coordinates changing,

Comparing these two we get the slop of line B as 2.

A thing you need to know here that product of slopes of a line perpendicular to another is -1.
Using this relation,

The slope of line a will be -1/2.

Let A pass through a coordinate (x,y).

Now,

Slope will be give by,
$\frac{y - 1}{x +2} = - \frac{1}{2} \\ y - 1= - \frac{x}{2} - 1 \\ y = - \frac{x}{2}$

20.
Option (A) is the correct one.

How?:

Equation of line B is y = 3x-1.

Once again using the general equation for a line,
y =mx+c
Slope of B will be 3.

Now for a pair of parallel lines their slopes are equal.

So,
Slope of A must also be 3.

Applying the generation equation for a line on A gives,

y = 3x+c

Since A is passing though coordinates (2,4) the values must satisfy this equation,

So we have,

$4 = 2(3) + c \\ c = 4 - 6 = - 2$
Now that we have value for c.
We can get the the equation we need.
So we have,

y = 3x -2.

Hope it helps.

5 0

4 years ago

Help its in the picture

docker41 [41]

Answer:

maybe 90%?

Step-by-step explanation:

if im wrong im sorry

5 0

3 years ago

Read 2 more answers

Consider the following hypothesis test:

postnew [5]

Answer:

a. P-value = 0.039.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to support the claim that the population mean significantly differs from 100.

b. P-value = 0.013.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to support the claim that the population mean significantly differs from 100.

c. P-value = 0.130.

The null hypothesis failed to be rejected.

At a significance level of 0.05, there is not enough evidence to support the claim that the population mean significantly differs from 100.

Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that the population mean significantly differs from 100.

Then, the null and alternative hypothesis are:

$H_0: \mu=100\\\\H_a:\mu\neq 100$

The significance level is 0.05.

The sample has a size n=65.

The degrees of freedom for this sample size are:

$df=n-1=65-1=64$

a. The sample mean is M=103.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=11.5.

The estimated standard error of the mean is computed using the formula:

$s_M=\dfrac{s}{\sqrt{n}}=\dfrac{11.5}{\sqrt{65}}=1.4264$

Then, we can calculate the t-statistic as:

$t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{103-100}{1.4264}=\dfrac{3}{1.4264}=2.103$

This test is a two-tailed test, with 64 degrees of freedom and t=2.103, so the P-value for this test is calculated as (using a t-table):

$\text{P-value}=2\cdot P(t>2.103)=0.039$

As the P-value (0.039) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to support the claim that the population mean significantly differs from 100.

b. The sample mean is M=96.5.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=11.

The estimated standard error of the mean is computed using the formula:

$s_M=\dfrac{s}{\sqrt{n}}=\dfrac{11}{\sqrt{65}}=1.3644$

Then, we can calculate the t-statistic as:

$t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{96.5-100}{1.3644}=\dfrac{-3.5}{1.3644}=-2.565$

This test is a two-tailed test, with 64 degrees of freedom and t=-2.565, so the P-value for this test is calculated as (using a t-table):

$\text{P-value}=2\cdot P(t$

As the P-value (0.013) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to support the claim that the population mean significantly differs from 100.

c. The sample mean is M=102.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=10.5.

The estimated standard error of the mean is computed using the formula:

$s_M=\dfrac{s}{\sqrt{n}}=\dfrac{10.5}{\sqrt{65}}=1.3024$

Then, we can calculate the t-statistic as:

$t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{102-100}{1.3024}=\dfrac{2}{1.3024}=1.536$

This test is a two-tailed test, with 64 degrees of freedom and t=1.536, so the P-value for this test is calculated as (using a t-table):

$\text{P-value}=2\cdot P(t>1.536)=0.130$

As the P-value (0.13) is bigger than the significance level (0.05), the effect is not significant.

The null hypothesis failed to be rejected.

At a significance level of 0.05, there is not enough evidence to support the claim that the population mean significantly differs from 100.

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3 years ago

Sakima Lena is employed at a restaurant. He has family medical coverage through the company’s group medical plan. The annual cos

omeli [17]

Answer: $2405

Step-by-step explanation: explanation is in the attached picture file

3 0

3 years ago