Short description: Two graphs titled, diagram 1 and diagram 2. Long description: In each graph, the horizontal axis represents the quantity and the vertical axis represents the price. The first graph shows a decreasing line representing demand that passes through points, A, B, and C. The line starts at a point near the top-left of the graph and ends at a point near the bottom-right. The second graph shows a concave up decreasing curve representing demand. The curve starts at a point near the top-left of the graph and ends at a point near the bottom-right. FIGURE 4-1 Refer to Figure 4-1, which shows two demand curves, one linear and the other a rectangular hyperbola. The price elasticity of demand is equal to one along the entire demand curve in a. diagram 2 only. b. diagram 1 only. c. neither diagram. d. both diagrams