If A=1,2A = \\{1, 2\\}A=1,2 and B=2,3B = \\{2, 3\\}B=2,3, what is AcupBA \\cup BAcupB (scale 6)?
1,2,3\\{1, 2, 3\\}1,2,3
emptyset\\emptysetemptyset
2\\{2\\}2
1,3\\{1, 3\\}1,3