We don't know the upper bound of h(n). Therefore nothing can be said about upper bound of given expression.Also lower bound of f(n) & g(n) are n.
f(n).g(n) = $\Omega{(n^{2})}$
And, h(n) = $\Omega{(n)}$ ,
Therefore expression would give $\Omega{(n^{2})}$