Suppose the price of a stock is $50 a share. A call option on the stock with four months until expiration date and exercise price $58 sells for $3. A put on the stock with the same strike price and expiration date sells for $7.
A. How much would a risk-free zero-coupon bond with maturity 4 month and face value $58 cost?
B. What is the bond equivalent and the effective annual yield of this type of bond?