I'm in pretty much the same boat as you when it comes to remembering stuff over the summer >__< Although I recognize the questions, it's hard to remember how to do them right away.
Anyway, I went to today's tutorial, so here's the solution to question 1:
83.87% of C
10.486% of H
5.59% of O
if you'd like me to give a rough summary of the steps I can do that as well
edit: I think the solutions are also being posted sometime next week, can't remember. it probably says on avenue though.