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5. [-/1 Points] DETAILS HARMATHAP12 9.4.047.NVA Suppose that a wholesaler expects that his monthly revenue, in dollars, for an electronic game wi R(x) = 160x - 0.15x, 0 s x $ 800 where x is the number of units sold. Find his marginal revenue and interpret it when the quantity (a) x = 400 Interpret the marginal revenue. The sale of the 400th unit results in a loss of revenue of this amount. O This is the additional revenue from the 400th unit. O The sale of the 401st unit results in a loss of this amount. O This is the additional revenue from the 401st unit. (b) x = 800 Interpret the marginal revenue. O This is the additional revenue from the 400th unit. O The sale of the 800th unit results in a loss of revenue of this amount. The sale of the 801st unit results in a loss of this amount. O This is the additional revenue from the 801st unit. 6. [-/1 Points] DETAILS HARMATHAP12 9.5.003. Find the derivative and simplify. y = (2x7 + 5)(6x6 - 7x# - 5) dx 7. [-/1 Points] DETAILS HARMATHAP12 9.5.009. For the function y = (x7+ 4)(x] - 4x), at (-2, 0) find the following. (e) the slope of the tangent line (b) the instantaneous rate of change of the function