If the distribution of x is normal then the sample mean will also be normal.

It will have mean and st.dev

Commit this to memory.

Let's do these a couple at a time.

First you need to know that

For a) You need to find

Using your answer in a) as , b) is binomial where Y is the amount of bags so Y~Bi(n,p) = Y~Bi(5,p)

Now find

Post your workings.