COMPOUND INTEREST If $10,000 is invested at an annual rate r (expressed as a decimal) comp...

COMPOUND INTEREST If $10,000 is invested at an annual rate r (expressed as a decimal) compounded weekly, the total amount (principal P and interest) accumulated after 10 years is given by the formula

a. Find the rate of change of A with respect to r.

b. Find the percentage rate of change of A with respect to r when r = 0.05 (that is, 5%).