Northern Airlines issued 25-year bonds with a maturity value of $3 million. Which statement is true if the bonds were issued at a premium? Select one: a. The cash rate of interest exceeded the coupon rate. b. The effective or yield rate of interest was greater than the maturity value of the bonds. c. The effective or yield rate of interest exceeded the coupon rate. d. The effective or yield rate of interest was less than the coupon rate