Problems 113–122 are based on previously learned material. The purpose of these problems is to keep the material fresh in your mind so that you are better prepared for later sections, a final exam, or subsequent courses such as calculus.

State the domain and range of the relation given below. Is the relation a function?
{(5, −3), (4, −4), (3, −5), (2, −6), (1, −7)}