A campground says campers can rend a square space taking up 225 square feet. How long would one side of the space be? feet

Ineed with number 17 i don’t get it at alll

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

Can any one me with the answers to these questions asap?