Answer
$8 \pi^2$
Work Step by Step
Since, $dS=\sqrt{(\dfrac{dx}{dt})^2+(\dfrac{dy}{dt})^2} dt$
Thus, $dS=\int_{0}^{2\pi} \sqrt{(-\sin t)^2+( \cos t)^2}=1$
or, $S=\int_{0}^{2\pi} (2 \pi)(2+\sin t)(1) dt$
Thus,
$S=[(2 \pi)(2t-\cos t)]_{0}^{2\pi} =8 \pi^2$