s $1,000 Preston Corporation has a bond outstanding with an annual interest payment of $80, a market price of $1,230, and a maturity date in 5 years. Assume the par value of the bond is $1,000 Use the approximation formula to compute the approximate yield to maturity and use the calculator method to compute the exact yield to maturity. Do not round intermediate calculations. Input your answers as a percent rounded to 2 Find the following: decimal places.) a. Coupon rato b. Current yield c-1. Approximate yiold to maturity e-2. Exact yield to maburity