The Figure Below Shows the Demand Schedule and Demand Curve

The figure below shows the demand schedule and demand curve for a product produced by a single-price monopolist. FIGURE 10-1
-Refer to Figure 10-1.Suppose this single-price monopolist is initially selling 9 units at $4 each and then reduces the price of the product to $3.By making this change,the firm is giving up revenue of ________ on the original number of units sold and gaining revenue of ________ on the additional units sold.Its marginal revenue is therefore ________.(All figures are dollars)

A) 40; 27; -13
B) 30; 36; 6
C) 34; 28; -6
D) 9; 3; -6
E) 3; 9; 6