The angle between vector $\vec{Q}$ and the resultant of $(2\vec{Q} + 2\vec{P})$ and $(2\vec{Q} - 2\vec{P})$ is:\\
(1) $\tan^{-1}\frac{(2\vec{Q} - 2\vec{P})}{2\vec{Q} + 2\vec{P}}$\\
(2) $0^{\circ}$\\
(3) $\tan^{-1}(\mathrm{P}/\mathrm{Q})$\\
(4) $\tan^{-1}(2Q/P)$