Warren Corporations stock sells for $40 per share. The company wants to sell some 10-year maturity, semi-annual annual coupon payments bond at $1,000 (par value). Each bond would have 30 warrants attached to it, each exercisable into one share of stock at an exercise price of $45. The firms straight bonds yield to maturity is 10%. Each warrant is expected to have a market value of $4 given that the stock sells for $42. What annual coupon rate must the company set on the bonds in order to sell the bonds-with-warrants at par value?