Self Test

Perfect Competition and the Coal Industry

Circle whether the following statements are True or False. 

Click on True or False to test your knowledge of the chapter.

You can check your answers at http://www.mines.edu/Academic/courses/econbus/dahl/ebgn530/st02/st02.htm

Remember for questions requiring the use of models to answer, it is often helpful to draw a graph so you can picture what is going on in the market.

1. True False The fundamental problem in economics is to allocate scarce resources across competing uses.

2. True False Allocating goods, services, and resources is only done by private markets.

3. True False In a perfectly competitive market, producers have control over the market price but consumers have no control over the market price.

4. True False Economists tend to always prefer the private market for the allocation of goods, services, and resources.

5. True False Exxon Coal U.S.A, Inc. is the largest US coal producer

6. True False Lignite is the coal form with the highest energy content

7. True False Long wall mining can be used when a coal seam is narrow and irregular.

8. True False About one third of the world's electricity is generated by coal.

Use the following competive model of the coal market to answer the following three questions.

Qd = 100 - 2Pc + 0.5Psb - 3Pcm + 0.1Y

Qs = -10 + 2Pc - 1Pk - 0.2Pl - 0.4Pnr

Where:   Pc = the price of coal,

Psb = the price of a substitute to coal such as natural gas = 15,

Pcm = a complement to gas consumption such as a gas boiler or gas range = 10,

Y = a measure of economic activity = 100,

Pk = the price of capital = 2,

Pl = the price of labor = 3,

Pnr = the price of other natural resources used in production of coal = 5.

9. True False The inverse supply equation at the above variable values is Pc = 7.3 - 0.5Qs.

10. True False Equilibrium price and quantity in the above model are Pc= 25.525, Q = 36.450.

11. True False If income increased in this market, it would increase demand, increase price, and increase supply.

12. True False Suppose the U.S. Fed tightened the money supply to raise interest rates and choke off inflation. If this raised the cost of capital, it would decrease supply, raise price, and lower quantity demanded.

13. True False If the price of capital increased lowering supply and income increased raising demand, then price would increase but the direction of the quantity change would be uncertain.

14. True False In a market where Qd = 87.5 - 2Pc and Qs = -14.6 + 2Pc, there would be excess supply below equilibrium price. This excess supply would drive prices down further and the market would be unstable.

15. True False Suppose Qd = 87.5 - 2Pc and Qs = -14.6 + 2Pc, at a price of 30, there would be excess quantity demanded of 17.9 units.

16. True False Let Qd = 87.5 - 2P and Qs = -14.6 + 2P. One way to a minimum price of $30 would be for the government to buy 17.9 units.

17. True False Quantity of coal demanded is Positively related to the number of buyers and negatively related to the price of coal.

18. True False If Qd = 87.5 - 2Pc and Qs = -14.6 + 2Pc, then the elasticity of supply at equilibrium price is about 1.40.

19. True False If Qd = 87.5 - 2Pc and Qs = -14.6 + 2Pc, then the elasticity of demand at equilibrium price is about 1.40.

20. True False Let Qd = 115 - 2Pc + 0.1 Y, Y = 100, with equilibrium price and quantity of Pce = 44.274, Qe = 36.45. The income elasticity of demand at equilibrium price suggests that oil is a luxury good.

21. True False Let Qd = 80 - 2Pc + 0.5 Psb, Psb =15 with equilibrium price and quantity of Pce= 25.525, Qe = 36.45 The cross price elasticity of demand for oil with respect to the price of a substitute at equilibrium is about 0.21.

22. True False Suppose the minimum price elasticity of demand for natural gas is -0.6. If the price of natural gas falls by 10% in France, the quantity demanded of natural gas would increase by 6%.

23. True False Suppose gas consumption in France is 38 billion cubic meters a year and the income elasticity of demand for gas is 0.5. If income in France fell by 1%, you would forecast demand for natural gas in France to be 39 billion cubic meters per year.

Use the following information to answer the next four questions. The consumption of natural gas in France is 38 billion cubic meters a year, the price is 750 FF per 1000 cubic meters, and France's income is 8 trillion FF per year. The own price elasticity of natural gas in France is -0.6 and the income elasticity of demand is 0.5.

24. True False A linear demand for natural gas compatible with the above information would be Q = 41.8 - 0.03P + 2.375Y.

25. True False A multiplicative or a log linear demand for natural gas in France would be Q = 22.18P-0.6Y0.5

26. True False If your demand equation is Q = 2 - 3lnP + 4Y, then your own price elasticity of demand is -3/Q.

27. True False You want to analyze a tax and need a demand equation of the form Qd = a + bP and a supply equation of the form Qs = c + dP.  You have found a study that gives the price elasticity of demand and supply of coal as -0.5 and +0.6,respectively .  The current consumption of coal in the U.S. is about 1 billion short tons and the average price for bituminous coal is about $25 per short ton.  Your  demand and supply equations would be Qd = 1.5 - 0.02P and Qs = 0.4 + 0.24P.

28. True False A positive cross price elasticity of demand implies that goods are complements.

29.  True False You would expect the household cross price demand elasticity between natural gas and electricity to be positive.