1. In general there is an __________ relationship between height/strength of the barriers and the number of firms in an industry

c.constant 

d.random

2. The main differences between perfect competition and monopolistic competition is

a. the number of sellers in a market

b. the ease of exit from the market

c. the difference in the firms profits in the long run

d. the degree of product differentiation

3. Mutual interdependence occurs when 

a. all firms in an industry are effected by the same macro-economic conditions, such as a recession, inflation, interest rates, exchange rates etc...

b. the actions of the firms are interdependent of one another

c. the actions of one firm in an industry are easily recognized and perhaps copied by others

d. Monopolistic recognize that they must face eventual competition in the long run

4. Firms in monopolistic competition would 

a. persistently realize economic profits in both the short and long run

b. May realize economic profits in the long run and normal profits in the short run

c. tend to incur persistent losses in both the short and long ru

d. tend to realize economic profits in the short run and normal profits in the long run.