Economist X. M. Gao and two colleagues have estimated that the cross-price elasticity of demand between beer and spirits is 0.15 If so, then beer and spirits are substitutes Gao and colleagues have estimated that the cross-price elasticity of demand between beer and wine is 0.31 If the price of wine increases by 10 percent, then the quantity of beer demanded will ▼| by □ percent. (Enter your response rounded to one decimal place.) In addition, Gao and colleagues have estimated the income elasticity of demand for beer to be 0.09 If so, then beer is 0 A, a luxury that may be a normal good or an inferior good. O B. a normal good that is a necessity 0 C, an inferior good O D. a normal good that may be a luxury or a necessity O E. a normal good that is a luxury