debt of $42000 is repaid by making payments of $4500. If interest is 9% compounded monthly, for how long will payments have to be made at the end of every six months? What payment made at the end of each year for 18 years will amount to $48000 at 4.2% compounded monthly?

What payment made at the end of each year for 18 years will amount to $48000 at 4.2% compounded monthly?