Automobile Production The number N of cars produced at a certain factory in 1 day after t hours of operation is given by N(t) = 100t – 5t2, 0 ≤ t ≤ 10. If the cost C (in dollars) of producing N cars is C(N) = 15,000 + 8000N, find the cost C as a function of the time t of operation of the factory.