Problem 5. A 1000 par value bond pays annual coupons of 80 . The bond is redeemable at par in 30 years, but is callable anytime from the end of the 10th year at 1050. Based on her desired yield rate, an investor calculates the following potential purchase prices, P : - Assuming the bond is called at the end of the 10th year, P=957 - Assuming the bond is held until maturity, P=897 The investor buys the bond at the highest price that guarantees she will receive at least her desired yield rate regardless of when the bond is called. The investor holds the bond for 20 years, after which time the bond is called. Calculate the annual yield rate the investor earns