Refer to the following diagram of the open-economy macroeconomic model to answer the questions that follow. Graph (a) Graph (b) Panel a shows a graph of a straight line, decreasing linearly, and a second straight line, increasing linearly. The following values are marked on the vertical axis, from lowest to highest. 3%, 4%, and 5%. 4% is on level with the point of intersection, or equilibrium point, of the two lines. 3% lies below the equilibrium point, and 5% lies above the equilibrium point. Panel b shows a graph of a straight line, decreasing linearly. Graph (c) Panel c shows a graph of a straight line, decreasing linearly, and a vertical line that extends from the horizontal axis. The vertical line intersects the decreasing line somewhere to the right of its middle point. Refer to Figure 32-3. At an interest rate of 4 percent, the diagram indicates that a. national saving equals domestic investment. b. in the market for foreign-currency exchange the quantity of dollars supplied equals the quantity of dollars demanded. c. there is a surplus in the market for foreign-currency exchange. d. net capital outflow + domestic investment = national saving.