III. If a competitive industry is in long-run equilibrium, a decrease in demand causes firms to earn negative profit because the market price will fall below average total cost.
Explanation:
A perfect competition is characterised by many buyers who sell homogenous products.
All firms in a perfect competition earn zero economic profit in the long run because there are no barriers to entry or exit.
In the long run, equilibrium occurs at: P = LMC = LATC
If demand falls, prices would fall below average total cost and the firm would earn negative profit .
The marketing mix refers to the actions a company takes to market its product(s) and/or service(s). Typically, it acts as a framework for breaking down the four key components of marketing — product, price, place, and promotion.
