Question

Which relations are functions and which are not functions?

1. {(3, 7), (3, 6), (5, 4), (4, 7)}
2. {(1, 5), (3, 5), (4, 6), (6, 4)}
--- AB


3. {(2, 3), (4, 2), (4, 6), (5, 8)}
--- AB


4. {(0, 4), (3, 2), (4, 2), (6, 5)}