Suppose that over the past year, the real interest rate was 3 percent, the cpi was 126.2 at the beginning of the year, and the cpi was 129.5 at the end of the year. it follows that a. the dollar value of savings increased at 5.6 percent, and the purchasing power of savings increased at 3 percent. b. the dollar value of savings increased at 3 percent, and the purchasing power of savings increased at 5.6 percent. c. the dollar value of savings increased at 0.4 percent, and the purchasing power of savings increased at 3 percent. d. the dollar value of savings increased at 3 percent, and the purchasing power of savings increased at 0.4 percent.