Bonnie purchased a 10 year bond on 1/1/2000. The bond was purchased to yield 4% per year convertible quarterly. The coupons are paid at 5% convertible quarterly. The bond is redeemable at par at the amount of 10,000. Bonnie received a coupon on 7/1/2005. What is the amortization of premium of the coupon she just received? 20.28 20.90 19.65 20.32 20.69