__. 19. A revenue function is given by R(x) = 6000x 0.42:3. wherex is the number of units sold. Find the marginal revenue when x = 50. a. 40,000 e. 300 b. 5000 f. 250,000 c. 3000 g. 500 d. 4000 11. Does not exist 20. The cost of producingx teddy bears per day at the Cuddly Companion Company is calculated by their marketing staff to be given by the formula C(x) =2so + 30x - 0.005x2. Evaluate the average cost 5000). at. $3,200.00 b. $29.50 0. $28.00 {1. $3,249.50 e. $32.00 21. Consider x) =10i 670'. (a) Find the intervals on which f is increasing or decreasing. (13) Find the local maximum and minimum values of f.' (c) Find the intervals of concavity and the inection points. (d) Using the information in (a), (b), and (c) to sketch a graph off 22. The cost, in thousands of dollars, of airing 2: television commercials during a Super Bowl game is given by the fonnula C(x) =- 250 + 1.500;: - 0.00223. Estimate how fast (in dollars per television commercial) the cost is going up when x = 8. a. $1,500 b. $1,500 c. $1,499,968 (1. $1,500,032 e. $1,499,984 23. Find the critical numberis) (ifany) and test them to determine ifx) = 3x' 40:3 + 9 has a local maximum or local minimum or neither at each critical number. 24. It takes money 20 years to triple at a certain rate of interest when compounded continuously. How long does it take for money to double at this rate