This is an Advance Macroeconomics problem set (3 questions)

Hello!
Take this post only if you can solve Advance Macro problems please!. I have a problem set of 3 questions. I attached their pictures down, one of them has the firs two questions, and the other picture has one question that says it’s#2, but that is actually #3.
please check it, and answer them in a clear hand writing please.