Which of the following, if true, would illustrate why price indexes such as the cspi might overstate inflation in the cost of going to college? check all that apply. a. as the price of calculators rose, fewer students decided to buy them, opting instead to use the free calculators in their cell phones or on their computers. b. professors required each student to buy 15 notebooks, regardless of the price. c. energy drinks became increasingly popular on college campuses between 2014 and 2016 due to significant improvements in flavor, but this quality change is hard to measure. d. a new mobile device for personal computing became available for purchase.