When the annual rate of inflation averages 4% over the next 10 years, the approximate cost C of goods or services during any year in that decade is given below, where t is the time in years and P is the present cost. C(t) = P(1.04) (a) The price of an oil change for your car is presently $22.24. Estimate the price 10 years from now. (Round your answer to two decimal places.) C(10) = $ (b) Find the rates of change of C with respect to t when t = 1 and t = 9. (Round your coefficients to three decimal places.) At t = 1 At t = 9 (c) Verify that the rate of change of C is proportional to C. What is the constant of proportionality?