a. When the price of a good falls, the consumer's real income _____________ (falls, rises, stays the same). This is an example of ________________ (an income effect, a substitution effect, perfectly inelastic demand). The household will buy ____________ (more, less, the same amount) of the good.

b. When the price of a good rises, the opportunity cost of the good ____________ (falls, rises, stays the same). This is an example of _________________ (an income effect, a substitution effect, perfectly elastic demand). The household will buy ____________ (more, less, the same amount) of the good.