$4)$ Bond J is a $4\%$ coupon rate bond. The K bond is a $10\%$ coupon rate bond. Both bonds have an $8-$year maturity, make semi$-$annual payments and have a yield to maturity of $9\%.$ If interest rates suddenly increase by $2\%,$ what is the percentage change in the price of these bonds? What if rates suddenly drop $2\%?$ What does this problem tell you about the interest rate risk of lower coupon bonds? Justify all of your response.