It's for a big test
laura & mary are doing their homework together.
mary thinks the relation {(1, 1), (1, 3), (2, 3), (3, 4)} is a function, but laura doesn’t think it is.
who is correct and why?

which ordered pairs are solutions for this function? {(0, -4), (1, -2), (5, 6), (6, 5)}

{(-4, 0), (0, 2), (1, 2), (4, 4)}

{(-3, 1), (0, -4), (2, 3), (3, 2)}

{(0, -4), (1, -2), (2, 0), (4, 4)}