The income-expenditure model assumes that the aggregate supply curve is horizontal at a given price level

If a monopoly situation arises from a perfectly competitive market, the portion of producer surplus that increases in a monopoly is transferred from the perfectly competitive market's

A) fixed cost. B) long-run positive economic profit. C) deadweight loss. D) consumer surplus.

When marginal revenue is zero for a monopolist facing a downward-sloping straight-line demand curve, the price elasticity of demand is:

a. equal to 1. b. equal to 0. c. greater than 1. d. less than 2.