I got stuck on the following problem:
Let $X_1 , \dots , X_n$ be iid from $N(\mu,\sigma^2)$. How can I obtain E$(\bar{X}/S)$, E$((\bar{X}/S)^2)$ and E$(\bar{X}^2)$, E$((\bar{X}^2)^2)$?
$\bar{X}$ is the sample mean and $S^2$ sample variance.
I've tried jacobian method for the first without success, and no idea on how to deal with the second.
Thanks for your help