uestion Completion Status: Demand for airline travel usually increases during the summer. One explanation is that O A. VIA Rail offers price discounts during the summer. O B. hotel prices rise during the summer. O C. there are more customers during the summer. O D. consumer incomes are lower in the summer and airline travel is a normal good QUESTION 2 Julia grows roses and tulips in her greenhouse. When she grows more roses and fewer tuli marginal O A. cost of growing roses decreases