This question asks to identify the equilibrium point for an individual firm, explain why the depicted market is short run, define the law of demand, and explain the term price takers.

Here are the answers to your questions:

4.11.1 The equilibrium point of an individual firm is where marginal cost (MC) equals marginal revenue (MR). In the graph for the individual firm, this occurs at point A.

• Point A

4.11.2 The graph depicts the short run because the individual firm is earning economic profits (Price = 10 > Average Cost = 8 at the equilibrium quantity). In the long run, economic profits would attract new entrants, driving profits to zero.

• Short run

4.11.3 The demand curve for the industry is downward sloping because of the law of demand. As the price of a good decreases, consumers are willing and able to purchase more of it, due to the income effect (increased purchasing power) and the substitution effect (the good becomes relatively cheaper than alternatives).

• The law of demand, which states that as price decreases, quantity demanded increases.

4.11.4 Businesses in this industry are referred to as price takers because they operate in a perfectly competitive market. In such a market, there are many small firms, homogeneous products, and perfect information. No single firm has enough market power to influence the market price, so they must accept the price determined by the overall industry supply and demand. This is reflected in the individual firm's horizontal demand curve (DD=AR=MR).

• They operate in a perfectly competitive market with many firms, homogeneous products, and no individual firm having market power to influence price.

4.11.5 When new entrants (businesses) join a perfectly competitive market, the industry supply will increase. This increase in supply will shift the industry supply curve to the right, leading to a decrease in the market equilibrium price. Consequently, the individual firm's demand curve (DD=AR=MR) will shift downwards, reducing economic profits until they reach zero (normal profits).

• New entrants will increase the industry supply, shifting the industry supply curve to the right. This will lead to a decrease in the market equilibrium price, causing the individual firm's demand curve to shift downwards until economic profits are eliminated.