Suppose the price of peanut butter falls from $3 to $2 per jar. Instructions: Round your answer to three decimal places and include a negative sign if appropriate. a. The quantity of jelly purchased falls from 15 million jars to 10 million jars. The cross-price elasticity of demand between peanut butter and jelly using the mid-point method is The goods are substitutes b. The quantity of jelly purchased rises from 10 million jars to 15 million jars. The cross-price elasticity of demand between peanut butter and jelly using the mid-point method is The goods are complements v