4. Consider an economy described by the following equations: Y =C+I+ G+ X (Income identity) C - 400 + 9 Ya (Consumption) with investment I = $300, government spending G = $100, net exports X = $100, and the tax rate t = .5. a, What is the level of income when spending balance occurs? What is the multiplier? b. Suppose government spending increases to $200. What is the new level of income