Answer:
Mean of sampling distribution = 25 inches
Standard deviation of sampling distribution = 4 inches
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 25 inches
Standard Deviation, σ = 12 inches
Sample size, n = 9
We are given that the distribution of length of the widgets is a bell shaped distribution that is a normal distribution.
a) Mean of the sampling distribution
The best approximator for the mean of the sampling distribution is the population mean itself.
Thus, we can write:

b) Standard deviation of the sampling distribution

Another way to ask this question: where the x-value of function g equals 12, what's the y-value?
remember that function notation is like so: f(x), g(x), h(x)... so the number in the parentheses is an x-value from the function.
look through your points and find the one that represents an x-value of 12. (12, 19) is the point, and 19 is your output--so, g(12) = 19.
If one pint was in 3 bags equally each bag would have 10.67 ounces.