Can you help me with 1 a,b,c please?

1a)

1b)

1c)

A $20,000, 8.1% bond redeemable at par is purchased 7.5 years before maturity to yield 6.7% compounded semi-annually. If the bond interest is payable semi-annually, what is the purchase price of the bond? The purchase price of the bond is $ (Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.) A $100,000 bond bearing interest at 6.5% payable annually is bought eight years before maturity to yield 6.9% compounded quarterly. If the bond is redeemable at par, what is the purchase price? The purchase price of the bond is $ (Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.) A 25-year bond issue of 5,300,000 and bearing interest at 5% payable annually is sold to yield 5.15% compounded quarterly. What is the issue price of the bonds? The purchase price of the bond is $ (Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.)