Iwill give you a medal if you can answer this question. the local skating rink pays mary a fixed rate per pupil plus a base amount to work as a skating instructor. she earns $90 for instructing 15 students on monday afternoon. last friday, she earned $62 for working with 8 students. lisa is also a skating instructor. she receives half the base amount that mary does, but she is paid twice as much per student. who would earn more money instructing a class of 20 students?