What is the distinction between exogenous variables and endogenous variables? O "Exogenous variables are left out of the model, while endogenous variables are included in the model" O "Endogenous variables are left out of the model, while exogenous variables are included in the model" "Endogenous variables can be demonstrated to be true empirically, while exogenous cannot." O "When constructing a model of reality, endogenous variables are usually assumed to stay constant" O Both (a) and (d) are trueWhich of the following describes the use of Keynesian macroeconomic policy to resolve an inflationary gap problem in the economy? O "Unemployment, resulting from the short-run product markets equilibrium being below Long-run Aggregate Supply (LRAS), causes wages to decline, which increases short-run Aggregate Supply (AS), until long-run equilibrium is attained at full employment level of income and a lower price level." "Government spending is increased, increasing Aggregate Demand (AD) to a level sufficient to attain long-run equilibrium at full employment level of income and a higher price level." "In attempting to produce beyond the economy's natural level of GDP, producers bid up wages and prices of other resources, causing the short-run Aggregate Supply (AS) to decrease to the point where long-run equilibrium is restored." O Taxes are increased reducing Aggregate Demand (AD) to a level consistent with full employment.Which of the following describes the way in which the self-correcting mechanism of the economy resolves the problem of a recessionary gap? "The recessionary gap is cured by an increase in government purchases of goods and services, which implies a shift to the right of the AD curve until full employment equilibrium is reestablished." "The unemployment associated with a recessionary gap causes wages to fall, increasing Aggregate Supply and thus shifting the AS curve to the right until a full employment equilibrium is reestablished. " "The unemployment associated with a recessionary gap causes a decrease in Aggregate Supply, shifting the AS curve to the left until full employment equilibrium is restored." Both (a) and (b) are correct. None of the above