Final answer:
When the national income in other nations decreases, it typically leads to a decrease in aggregate demand in our economy due to a decrease in foreign demand and a relative price increase of U.S. goods.
Step-by-step explanation:
When the national income in other nations decreases, it typically leads to a decrease in aggregate demand in our economy. This is because a decrease in foreign demand and a relative price increase of U.S. goods contribute to a decrease in aggregate demand. Changes in net exports caused by recessions in other nations can also impact a nation's level of real GDP in the short run.