V=(4/3)(pi)(r^3)
r=7
Hope this’ll help
Answer:

Now we can calculate the p value with the following probability

If we use the commonly significance level of 0.05 we see that the p value is lower than these values we can conclude that the true mean is different from the value of 465.6 at 5% of significance
Step-by-step explanation:
Data provided
represent the mean score on the standardized memory test
represent the population standard deviation
sample size
represent the value that we want to verify
z would represent the statistic
represent the p value
System of hypothesis
We are interested to check if the memory performance for elderly individuals differs from that of the general population (mean different from 465.6), the system of hypothesis are then:
Null hypothesis:
Alternative hypothesis:
Since we know the population deviation we can use the z statistic from the z test for the true mean:
(1)
Replacing the info given we got:

Now we can calculate the p value with the following probability

If we use the commonly significance level of 0.05 we see that the p value is lower than these values we can conclude that the true mean is different from the value of 465.6 at 5% of significance
<h3>
Answer: 6 inches</h3>
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Explanation:
x = amount (in inches) the spring is stretched
y = force applied (in pounds)
y = kx for some constant k, since x and y vary directly
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Plug in the given info that x = 5 and y = 150 pair up together
Solve for k
150 = k*5
150/5 = k
k = 30
The equation goes from y = kx to y = 30x. Whatever the stretching distance (x) is, you multiply by 30 to get the force needed (y) to pull the spring.
---------------
Plug in y = 180 to solve for x
y = 30x
180 = 30x
30x = 180
x = 180/30
x = 6
The spring will be stretched 6 inches if you apply a force of 180 pounds.
Here we have one large triangle with two smaller triangles drawn inside. The two smaller triangles are similar.
Thus, a/12 = 12/16, or a/12 = 3/4, or 4a=36, or a = 9.
Find b in the same way: b/20 = 9/12 (and so on).