Let \(D\) be an open set in \(\mathbb C\). Let \(\mathcal F\) be a collection of holomorphic functions defined on \(D\).
(a) Assume \(\mathcal F\) is uniformly bounded on the boundary \(\partial \Delta \) of each triangle \(\Delta \) contained in \(D\). Show that \(\mathcal F\) forms a normal family.
(b) Is \(\mathcal F\) a normal family if we assume it is uniformly bounded when restricted to any interval contained in \(D\)?