Note error in question 4 book problem 4.9
it should read X=2 * sin (z/4)

Problem 1)

How do you solve for E(x^2) because you have to know that in order to solve for E(Y^2)?

Remember that Var(x) = E(x^2) - m^2 So...E(x^2) = Var(x)+ m^2 Since you have both Var(x) and m (mean) you can solve for E(Y^2). Now maybe you can help me with problem 8.

Problem 8)

We are given that it is a Poisson R.V. but the a and b that are given are decimals (.2 and 4.2 respectively). Can you just assume that we only need to evaluate from 1 to 4 because only the points 1, 2, 3, and 4 fall between those points?

Yes, you are able to make that assumption. We also learned in the help session that on that problem since you are not given a time you are able to assume it is 1 so that lambda = alpha.