Volume of the solid of revolution 

I need help with the following two problems. Thanks!

(a) Find the volume of the solid obtained by rotation tha region bounded by the graphs of $y=x^2$ and $y=x^4$ about $y$-axis. 
(b) Find the volum of the solid obtained by rotating the graph of $y=\sin x$ about $x$-axis. 

Answer

Answers can be viewed only if
  1. The questioner was satisfied and accepted the answer, or
  2. The answer was disputed, but the judge evaluated it as 100% correct.
View the answer

1 Attachment

The answer is accepted.