If G = {7, 8} and

Given: G = {7, 8} and H = {5, 4, 2}

By definition of Cartesian product of two non-empty Set P and Q:

P × Q = {(p, q): p Є P, q Є Q}

Therefore, G × H = {(7,5), (7,4), (7,2), (8,5), (8,4), (8,2)}.

And H × G = {(5,7), (5,8), (4,7), (4,8), (2,7), (2,8)}.