When a typical firm in a perfectly competitive industry is earning profits, in that case: w) all firms will carry on earning profits. x) new firms will enter into the long run causing market supply to reduce, market price to rise and profits to raise. y) new firms will enter into the long run causing market supply to raise, market price to fall and profits to reduce. z) the number of firms in the industry will keep constant within the long run.
How can I solve my economics problem? Please suggest me the correct answer.