A function is a relation in which no two ordered pairs have the same first element. A function associates each element in its domain with one and only one element in its range. Solution: a) A = {(1, 2), (2, 3), (3, 4), (4, 5)} is a function because all the first elements are different.
Your distance is 1424 and your rate is 356. As you said, d = r*t. Since you don't have the time you would do 1424 divided by 356. This leaves you with a time of 4 hours. (Don't forget units!)
