Answer:
c. Income elasticity is 69 and the good is an inferior good.
Explanation:
Income elascitiy = percentage change in quantity demanded / percentage change in income
9% / 13% = 0.69 = 69%
An inferior good is a good whose demand falls when income increases and whose demand increases when income falls. When sunnys income increased, she reduced her demand for hamburgers.
A normal good is a good whose demand increases when income increases.
Cross price elasticity of demand measures the responsiveness of quantity demanded of good A to changes in price of good B.
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