Professor, how to calculate this problem?

hello professor,
why the answer is D? i feel it will occur. Could you please explain about this option？

Why input price would fixed in short run？

Dear lin: What is the relationship between aggregateexpenditure, aggregate demand and aggregate supply?

Why C is not correct? nation income increase, where is additonal money?

1Should we think about investment= saving, the demand shfit to right, or 2 investment make supply shift to right,

why the inflation will not have an effect on the AD curve? the inflation will cause the higher price level and make the real GDO decrease.

why we should choose A as answer?

Hello, Lin! What's the difference between unexpected changes and expected changes in the prices of an important natural resource in this qusetion?

Dear lin: the book said higher price level will reduce the net exports, but I think high price level can be caused by inflation(then the currency devalue), and currency devaluation is good for export. So why the net exports still decrease?

could you explain why price level doesn't effect the long run AS? I mean, why firms don't have incentive to produce more?

does the long-run macroeconomic equilibrium not change?