A $$50,000$ loan at $7\%$ compounded semi$-$annually requires three payments at $3$ years, $4$ years, and $5$ years. The first payment is $$12,500$ and the second payment is four times as large as the final payment.

For full marks your answer$($s$)$ should be rounded to the nearest cent.

a$.$ Calculate the value of the third payment on the loan.

Payment:

b$.$ Calculate the value of the second payment on the loan.

Payment: