State four barriers to entry in a monopoly market. Sketch a diagram showing price rigidity under oligopoly.

a) The statistics include consumption expenditure, investment, government spending, and income tax. The presence of government spending and income tax indicates a government sector. Since exports and imports are not initially mentioned, the economy is a closed economy with a government. b) Step 1: Determine disposable income (Y^d) and the consumption function. Given Y^d = Y - T and T = 0.5Y. Y^d = Y - 0.5Y = 0.5Y Substitute Y^d into the consumption function C = 60 + 0.8Y^d: C = 60 + 0.8(0.5Y) = 60 + 0.4Y Step 2: Set up the equilibrium condition for a closed economy with government. Y = C + I + G Substitute the given values: Y = (60 + 0.4Y) + 200 + 400 Step 3: Solve for the equilibrium level of national income (Y). Y = 660 + 0.4Y Y - 0.4Y = 660 0.6Y = 660 Y = (660)/(0.6) Y = 1100 million francs CFA c) Step 1: Introduce exports (X) and imports (M) into the equilibrium condition. Given X = 300 and M = 0.2Y. The economy is now an open economy with government. Y = C + I + G + (X - M) Substitute the consumption function from part (b) and the new values: Y = (60 + 0.4Y) + 200 + 400 + (300 - 0.2Y) Step 2: Solve for the new equilibrium level of income (Y). Y = 60 + 0.4Y + 200 + 400 + 300 - 0.2Y Y = (60 + 200 + 400 + 300) + (0.4Y - 0.2Y) Y = 960 + 0.2Y Y - 0.2Y = 960 0.8Y = 960 Y = (960)/(0.8) Y = 1200 million francs CFA d) Step 1: Identify the components for the multiplier in an open economy with proportional tax. From C = 60 + 0.8Y^d, the marginal propensity to consume (MPC) from disposable income is 0.8. From T = 0.5Y, the tax rate (t) is 0.5. From M = 0.2Y, the marginal propensity to import (MPM) is 0.2. Step 2: Calculate the value of the multiplier (k). The formula for the multiplier is: k = (1)/(1 - MPC(1-t) + MPM) k = (1)/(1 - 0.8(1-0.5) + 0.2) k = (1)/(1 - 0.8(0.5) + 0.2) k = (1)/(1 - 0.4 + 0.2) k = (1)/(0.6 + 0.2) k = (1)/(0.8) k = 1.25 e) (i) Balance of payment situation Step 1: Calculate total imports (M) at the new equilibrium income from part (c), Y = 1200. M = 0.2Y = 0.2(1200) = 240 million francs CFA Step 2: Calculate net exports (X - M). X - M = 300 - 240 = 60 million francs CFA Since net exports are positive, the country has a balance of payments surplus. (ii) Budget situation Step 1: Calculate total tax revenue (T) at the new equilibrium income from part (c), Y = 1200. T = 0.5Y = 0.5(1200) = 600 million francs CFA Step 2: Calculate the government budget balance (G - T). G - T = 400 - 600 = -200 million francs CFA Since government spending is less than tax revenue, the country has a budget surplus. f) An inflationary gap occurs when the actual aggregate demand in an economy is greater than the aggregate supply at full employment. This leads to upward pressure on prices and inflation. A deflationary gap occurs when the actual aggregate demand is less than the aggregate supply at full employment, resulting in unused capacity, unemployment, and downward pressure on prices. Send me the next one 📸