Exhibit 17.9 A graph. Three lines are graphed on a coordinate plane. The horizontal axis is labeled Quantity of education. The following values are displayed on the horizontal axis from left to right: uppercase E prime and uppercase E prime. The vertical axis is labeled Dollars per unit. The first line labeled S, is upward sloping, begins at the bottom left of the viewing window, goes up and to the right, passes through a point labeled lowercase e at x = uppercase E, a point labeled lowercase e prime at x = uppercase E prime, and exits the top right of the viewing window. The second line labeled D, is downward sloping, begins at the top left of the viewing window, goes down and to the right, intersects the line S at the point labeled lowercase e, and exits the bottom right of the viewing window. The third line labeled D prime, is downward sloping, begins at the top left of the viewing window above the line D, goes down and to the right, passes through a point labeled lowercase b at x = uppercase E, intersects the line S at the point labeled lowercase e prime, and exits the bottom right of the viewing window, above the line D. A vertical dashed line begins on the horizontal axis at x = uppercase E, goes up and ends on the line D prime, at the point labeled lowercase b. The area on the graph under the line D prime, above the line S, and to the right of the vertical dashed line, is shaded. The area on the graph above the lines D prime and S, is labeled A. The area on the graph