Explain how each of the following illustrates one of our principles of economy-wide interactions.

a. The White House urged Congress to pass a package of temporary spending increases and tax cuts in early 2009, a time when employment was plunging and unemployment soaring.

b. With oil prices plummeting, Canadian and U.S. oil companies have been forced to shut down their productive wells. In cities throughout North Dakota, Wyoming, Texas, and Alaska, restaurants and other consumer businesses are failing.

c. In the mid-2000s, Spain, which was experiencing a big housing boom, also had the highest inflation rate in Europe.