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The following macroeconomic forecasts are provided for the country of Sovereignty imme- diately before and after it leaves the Ruritanian Union (RU), which is its biggest trading partner. Sovereignty leaving the RU has been dubbed Soxit by the media: Forecast Before Soxit After Soxit Consumer expenditure 0.75Y + 100 0.65Y + 80 Investment expenditure 350 310 Government expenditure 400 360 Exports 370 310 Imports 540 430 All amounts are in billion. Calculate the change in the equilibrium level of national income as a result of Soxit, both as an amount in billions and as a percentage change