Average Cost Jester Sports manufactures tennis rackets. The total cost of producing x rackets per hour is given by C(2) = 0.5 202 + 4.5 2 + 436. The average cost per racket at production level x rackets per hour is C(a) = - C(x) Use differential approximations to estimate the change in average cost per racket if the production is increased from 20 per hour to 22 per hour. Round to the nearest cent. $ per racket NOTE: Your answer may be negative