Not sure how to do these, any help will be appreciated.
for the first one , remember . the r goes from 2 -> 3 goes form o to 2pi. the z limit are from 0 to . order matters here, do the z integral first.
for the second one, use , using limits r going form 1 to 2 , form 0 o pi and form 0 to 2pi. and remember .
Bobak