Draw a single diagram of the Average Revenue

Draw a single diagram of the Average Revenue and Marginal Revenue curves of a firm which can sell any quantity of the good at a given price. Explain.

In a perfectly competitive market form, a uniform price prevails in the market, which is decided by the market forces of demand and supply.
Sellers can sell any number of units at that price. Uniform price results in constant AR and MR. Therefore, in this market form, price = AR = MR.