1. (4 points) A local charity collects data on their donors. For donors with income I, they compute the average yearly donation value D, to create the table below. I (thousands $) 80 100 120 140 D ($) 42.5 72.5 81.2 72.5 (a) Can we think of I as a function of D, or D as a function of I? Select all correct answers. O I is a function of D. D is a function of I. O Neither