A random sample of size 20 from a normal distribution with = 4 produced a sample

Question:

A random sample of size 20 from a normal with σ = 4 produced a sample mean of 8.
(a) Is the normal? Explain.
(b) Compute the sample test statistic z under the null hypothesis H0: μ = 7.
(c) For H1: μ ≠ 7, estimate the P-value of the test statistic.
(d) For a level of significance of 0.05 and the hypotheses of parts (b) and (c), do you reject or fail to reject the null hypothesis? Explain.
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...