please solve it in details

A ten-year 1000 par value bond with coupons paid annually at an annual rate of r is callable at par at the end of the 7 th, 8 th, or 9 th year. The price of the bond is 1023. If the bond is called in the worst-case scenario for the bond investor, the resulting annual effective yield rate, i, is 97% of r. Calculate i. 12.1% 14.0% 16.1% 17.6% 21.5%