Economists in Funlandia, a closed economy, have collected the following information about the economy for a particular year: Y = 10,000; C = 6,000; T = 1,500; G = 1,700. The economists also estimate that the investment function is: I = 3,300 - 100r where r is the country's real interest rate, expressed as a percentage. Calculate private saving, public saving, national saving, investment, and the equilibrium real interest rate.