Q19
Answer
Option 4
Aviator Alan's nonstop airline service from Seattle to Nome
The airline requires a significant cost, and it is a barrier to
entry in the market, so the airline industry is not perfectly
competitive.
A farm and beef are perfectly competitive industries as anyone can
enter the industry and there are many producers of the same.
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Q20
Answer
Option 1
perfectly elastic at the established market price
A perfectly competitive market has many firms with identical
product and consumer has perfect knowledge, so the firms have a
perfectly elastic demand curve.