The area enclosed by the closed curve $C$ given by the differential equation $\frac{dy}{dx} + \frac{x + a}{y - 2} = 0$, $y(1) = 0$ is $4\pi$. Let $P$ and $Q$ be the points of intersection of the curve $C$ and the $y$-axis. If normals at $P$ and $Q$ on the curve $C$ intersect $x$-axis at points $R$ and $S$ respectively, then the length of the line segment $RS$ is\\
(1) $2\sqrt{3}$\\
(2) $\frac{2\sqrt{3}}{3}$\\
(3) 2\\
(4) $\frac{4\sqrt{3}}{3}$