Answer:
A monopolist does not have a supply curve because price and quantity are decided at the same time.
Explanation:
A supply curve is generally upward sloping showing a direct relationship between the price level and quantity supplied. In case of a perfectly competitive market, the demand curve is a horizontal curve, showing marginal; revenue and average revenue. The firm here is a price taker and decides the quantity to be supplied according to the price level. The firm is able to maximize profit at the level of output where the price is equal to marginal cost.
However, in case of a monopoly, the firm is a price maker. There is no unique relation between price and quantity. The price and quantity to be supplied are determined at the same time at the point where marginal revenue is equal to marginal cost.