Any of you guys who feeling comfortable with anything of these?

Im really lost

You observe the following sample (rounded) drawn from a normal random variable

X~N(µ,ó²):

22, 19, 14, 15, 20, 20, 21, 14, 19, 18, 15, 14, 15.

a) Use the sample to estimate µ

and ó².

b) Estimate the variance of the sample average ó²ӿ

c) Find a 99% confidence interval for µ

d) Test the null hypothesis H0: µ15 against H0: µ ≠15 with α= 5%

e) Test the null hypothesis H0: µ=µ0 against H0: µ ≠µ with α= 5% for an arbitrary µ0.

f) Find the confidence interval for µ.

g) How are the results in e) and f) related? Why?

Im glad for all kind of answers!