Economists assume that business firms attempt to maximize their profits.

During a recession:

a. Government spending automatically rises and taxes automatically rise. b. Government spending automatically falls and taxes automatically rise. c. Government spending and taxes automatically fall. d. Government spending and taxes do not tend to change. e. Government spending rises automatically and taxes fall automatically.

For economists, substitutes for laboratory experiments often come in the form of

a. natural experiments offered by history. b. untested theories. c. "rules of thumb" and other such conveniences. d. reliance upon the wisdom of elders in the economics profession.