18. Compute the nominal annual rate of interest compounded semi-annually at which $515.00 paid at the end of every six months for seven years accumulates to $10,000.00.

he nominal annual rate of interest is ____% compounded semi-annually.

19. What is the nominal annual rate of interest compounded quarterly if a loan of $23,500 is repaid in eight years by payments of $1000 made at the end of every three months?

The nominal annual rate of interest is ____% compounded quarterly.