The zoom slingshot company's marketing department conducts a customer satisfaction survey. it discovers that one of its slingshot lines frequently breaks, causing customer dissatisfaction. the product is retooled to be stronger and customers are now happy. this is an example of marketing creating:

Which of the following statements is (are) true? i. free entry to a perfectly competitive industry results in the industry's firms earning zero economic profit in the long run, except for the most efficient producers, who may earn economic rent. ii. in a perfectly competitive market, long-run equilibrium is characterized by lmc < p < latc. 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.