Frank’s consumption of coffee just increased from 1 cup per day to 3.

You thenlearn the cause for this change, which is one of the reasons listed in a—e below.

For a—b,calculate Frank’s income elasticity of demand for coffee and determinewhether coffee is an inferior, normal, or luxury good; and for c—e, calculateFrank’s cross-price elasticity of demand between coffee and whichever other good is mentioned, and determine if they’re complements or substitutes.

a. Income goes from $16k to $20k annually.

Income goes from $6k to $24k annually.

The price of tea went from $4 per cup to $6.

The price of soda went from $2 per cup to $4.

The price of a jug of cream went from $5 to $1.