A majority of federal revenue once came from tariffs

Suppose that a firm operating in perfectly competitive market sells 200 units of output at a price of $3 each. Which of the following statements is correct? (i) Marginal revenue equals $3. (ii) Average revenue equals $600. (iii) Average revenue exceeds marginal revenue, but we don't know by how much

a. (i) only b. (iii) only c. (i) and (ii) only d. (i), (ii), and (iii)

A shift of the demand curve to the left represents

A) an increase in demand. B) a decrease in demand. C) an increase in quantity demanded. D) a decrease in quantity demanded.