math
posted by Beth .
The demand for the video game is modeled by the logistic curve, where q(t) is the total number of units sold t months after its introduction.
q(t)= 10000/(1+0.5 e**(0.4t))
(a) Use technology to estimate q'(4) to the nearest integer.
mark units per month
(b) Assume that the manufacturers of the video game sell each unit for $810. What is the company's marginal revenue dR/dq?
$ mark /unit
(c) Use the chain rule to estimate the rate at which revenue is growing 4 months after the introduction of the video game. (Round your answer to the nearest thousand.)
$ mark per month.

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