Use rotation to find area and real quadratic factors

In an Argand diagram, $P,Q$ represent $z_1=2+3i$ and $z_2=iz_1$.

(i) Find the area of triangle $OPQ$, where $O$ is the origin.2 marks

(ii) These numbers are roots of $(z^2+az+b)(z^2+cz+d)=0$, where $a,b,c,d\in\mathbb R$. Find $a,b,c,d$.4 marks