Problems refer to the following: Revenues from sweater sales in a sportswear chain are given approximately by
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where R(t) is the revenue (in thousands of dollars) for a month of sales t months after January 1
(A) What is the rate of change of revenue t months after January 1?
(B) What is the rate of change of revenue 3 months after January 1? 10 months after January 1? 18 months after January 1?
(C) Find all local maxima and minima for 0
(D) Find the absolute maximum and minimum for 0<=t<=24.
(E) Repeat part (C), using a graphing calculator.