economics chapter 9&10

Chapter 9

3. A study of the costs of electricity generation for a sample of 56 British firms in 1946-1947 yielded the following long-run cost function

AVC=1.24+.0033Q + .0000029Q² – .000046QZ – .026Z +.00018Z²

 Where ACV= average variable cost (i.e. working costs of generation) measured in pence per kilowatt-hour (kWh). (A pence was British monetary unit equal, at that time to 2 cent U.S)

Q= output, measured in millions of kWh per year

Z= plant size, measured in thousands of kilowatts

  1. Determine the long- run variable cost function for electricity generation
  2. Determine the long-run marginal cost function for electricity generation
  3. Holding plant size constant at 150,000 kilowatts, determine the short-run average variable cost and marginal cost function for electricity generation
  4. For a plant size equal to 150,000 kilowatts, determine the output level that minimizes short-run average variable costs
  5. Determine the short-run average variable  cost and marginal cost at the output level obtained in part (d)

4. Assuming that all other factors remain unchanged, determine how a firm’s break-even point is affected by each of the following.

a. The firm finds it necessary to reduce   the price per unit because of increased foreign completion

b. The firms direct labor costs are increased as the result of a new labor contract

c. The Occupational Safety and Health Administration ( OSHA) requires the firm to install new venting equipment in its plant. (Assume that this action has no effect on worker productivity)

5. Cool-Aire Corporation manufactures a line of room air conditioners. Its break-eve sales level is 33,000 units. Sales are approximately normally distributed. Expected sales next year are 40,000 units with a standard deviation of 40,000 units

a. Determine the probability that Cool-Aire will incur an operating loss

b. Determine the probability that Cool-Aire will operate above it break-even point.

Chapter 10

2. Television channel operating profits very from as high as 45 to 55 percent at MTV and Nickelodeon down to 12 to 18 percent at NBC and ABC. Provide a Porter Fuve Force analysis of each type of network. Why is MTV so profitable relative to the major networks?

6. Assume that a firm in a perfectly competitive industry has the following total cost schedule

OUTPUT (UNITS)                                           TOTAL COST ($)

  10                                                                         $110

  15                                                                          150

   20                                                                         180

   25                                                                          225

   30                                                                            300

    35                                                                         385

   40                                                                           480


  1. Calculate a marginal cost and an average cost schedule for the firm
  2. If the prevailing market price is $17 per unit, how many times will be produced and sold? What are profits per unit? What are total profits?
  3. Is the industry in long-run equilibrium at this price?

10. Which of the following products and services are likely to encounter adverse selection problems: golf shirts at travelling pro tournaments, certified gemstones from Tiffany’s graduation, gift travel package or mail-order auto parts? Why or why not?