An investor initially purchases a 5-year, 6% annual coupon payment bond at par value of $100. Assume the interest rates go up by 1% right after the first coupon is received and then go down by 2% right after the fourth coupon is received. Assume the term structure is flat and coupon payment are reinvested in zero-coupon bonds that mature at the end of investment horizon.

a) What is the investor's realized rate of return if he holds the bond until maturity?

b) What is the investor's realized rate of return if he sells the bond after four years?