Boeing produces commercial airliners. Assume that if Boeing produces 10 planes a year, its total costs are $500 million and that if produces 11 planes, its total costs are $560 million. The marginal cost of the 11th plane is:

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?