Average fixed cost is equal to a. total fixed cost divided by quantity. b. marginal cost minus average total cost. c. quantity divided by total fixed cost. d. the difference between average total cost and average variable cost. e. a and d

When a company produces and sells x thousand units per week, its total weekly profit is p thousand dollars, where upper p equals startfraction 800 x over 100 plus x squared endfraction . the production level at t weeks from the present is x equals 4 plus 2 t. find the marginal profit, startfraction dp over dx endfraction and the time rate of change of profit, startfraction dp over dt endfraction . how fast (with respect of time) are profits changing when tequals8?