Bill Christenson deposited $40,000 in his credit union on September 23, 1993. Recently, while going through some papers he discovered the account. Before going to the credit union, he searched their web site and learned that the interest rate on his deposit was 4.4%, compounded quarterly, during the first six years, then it increased to 4.68% compounded weekly for the next six years, and then dropped to 4.0%, compounded continuously, for the final ten years.

a. How much should Bill have in this account on September 23, 2015?

AND b. If Bill had invested in a twenty-two year certificate of deposit with a fixed rate of interest, what single annual rate of interest would Bill have needed to earn to be in the same position as in part a?