I need help with one of each. once I figure out how to do one, I can do the others. I'm supposed to leave pi in my answers except with spheres and that is what is throwing me. the other problems where I worked out the formulas without leaving pi in my answers I got correct. #8 I'm not supposed to leave pi in my answers but I still got it wrong.

You don't have to give me the answer if you do not want to but can you set up the problem for me?

Thanks! I need help with #3 here

and 5, 7, and 8 here