Question $2$: Deriving more expressions

This question builds onto the exam question... In class we said that the total drag is given by

$D=\frac{1}{2}{V}^{2}S{C}_{D_0}+\frac{W^2}{\frac{1}{2}{V}^{2}S}(\frac{1}{eAR})$

We derived expressions for $C_D$ and $C_L$ at minimum drag. Now derive an expression for the corresponding velocity at the point that minimizes total drag.