The amount of money Garrett will raise for charity by participating in a walkathon can be modeled by the linear function [math]d = 50m + 120[/math], for which [math]m[/math] is the number of miles he walks and [math]d[/math] is the number of dollars he raises. The value [math]120[/math] represents how much of his own money Garrett donated before the walkathon started. Find the domain and the range of this function.
