7. An economy has only two goods, apples and bananas. To compute the CPI for two or more consecutive years, we assume that a. the number of apples bought by the typical consumer is equal to the number of bananas bought by the typical consumer in each year. b. the percentage change in the price of apples is equal to the percentage change in the price of bananas from year to year. c. neither the number of apples nor the number of bananas bought by the typical consumer changes from year to year. d. neither the price of apples nor the price of bananas changes from year to year