Chet has $1200 invested in a bank account modeled by the function p(n)=1200(1.002)^n , where p(n) is the value of his account ,in dollars after months .Chet debt is modeled by the function Q(n)= 100n, where Q(n) is the value of debt , in dollars after n months. After n months ,which function represents chets net worth, R(n)?