Given A={1,2}A = \{1, 2\}A={1,2}, what is the set A×{a,b}A \times \{a, b\}A×{a,b}?
{(1,a),(1,b),(2,a),(2,b)}\{(1, a), (1, b), (2, a), (2, b)\}{(1,a),(1,b),(2,a),(2,b)}
{(1,1),(1,2),(2,1),(2,2)}\{(1, 1), (1, 2), (2, 1), (2, 2)\}{(1,1),(1,2),(2,1),(2,2)}
{(1,a),(2,b)}\{(1, a), (2, b)\}{(1,a),(2,b)}
{1,2,a,b}\{1, 2, a, b\}{1,2,a,b}