Find the modes of the following datasets.
4, 5, 5, 4, 1, 6, 8, 7, 9, 10, 3, 4
9, 19, 4, 6, 7, 3, 3, 5, 1, 5, 9, 4, 5
3, 5, 2, 2, 9, 9, 9, 4, 2, 5, 3, 2, 4, 4
7, 7, 3, 6, 1, 9, 19, 15, 3, 6, 14, 15, 4
5, 9, 9, 10, 3, 15, 3, 6, 6, 1, 10, 2, 10, 11
6, 1, 1, 9, 7, 5, 5, 7, 1, 4, 1, 8, 9, 1
3, 5, 1, 6, 9, 10, 4, 4, 6, 1, 4, 6, 3, 7