1. A motor corporation sells cars for P dollars, 40% of which must be paid in cash. The unpaid balance plus 8% of this balance is divided into equal monthly payments to be made for the following 15 months. What effective rate of interest is one actually paying when buying on this plan?

2. A set aside $500 annually in a trust fund which allows interest at 5% effective. What amount does A have to his credit just after the 15th deposit has been made?