7. AAA Agricultural Machinery decides to invest in new robots. The tax- capital is equal to 8. The expected marginal product of capital for the firm is MPKf = 20-0.1K. The firm currently has 100 units of capital. Suppose depreciation rate is 10%. What is the desired investment? 8. The desired consumption of a closed economy is given by ca = 100+0.7Y-140r, where Y is output, and r is the real interest rate. Suppose Y = 1500 and government purchase is 50. Given r, what is the expression for the desired saving of the economy? 9. Suppose that the economy-wide desired investment of a closed economy is 1d = 265-30r, where r is the real interest rate. The desired saving is so = 235+170r. What is the equilibrium real interest rate? 10. Suppose that the economy-wide desired investment of a small open economy is 1d = 240-150r, where r is the world interest rate. The desired saving is Sd = 220+100r. If the world interest rate is 5%, what is this country's current account balance? 11. Suppose there are two large open economies. The current account balance of country A is -30+400r, where r is the world interest rate. The current account balance of country B is -40+600r. What is the equilibrium world interest rate? 12. Suppose f(k) = 10.4, A = 2, s = 0.1, n = 0.04, and d = 0.1, what is the value of k in the steady state? (*Round to 2 decimal places*) 13. Suppose f(k) = 640.3, A = 1, s = 0.2, and capital per worker in the steady state is 10. What is consumption per worker in the steady state? (*Round to 2 decimal places*) 14. Suppose real money demand is given by L(Y, r) = 50 + 0.5Y - 100r, and real money supply is 95. What is the equilibrium interest rate in the asset market if Y = 100? 15. Suppose IS curve is given by Y = 2000 - 1000r and LM curve is given by Y = 4000r + 1000. What is the general equilibrium interest rate