Ans: A
I is true. Let $n$ be the number of sides of the regular polygon. Then we have
I is true. Let $n$ be the number of sides of the regular polygon. Then we have
$\begin{array}{rcl}
\dfrac{(n-2)\times180^\circ}{n} & = & 5 \times \dfrac{360^\circ}{n} \\
n-2 & = & 10 \\
n & = & 12
\end{array}$
Therefore, the regular polygon is a regular 12-sided polygon. Hence, the interior angle
$\begin{array}{cl}
= & \dfrac{(12-2) \times 180^\circ}{12} \\
= & 150^\circ
\end{array}$
II is not true. The number of diagonals of the polygon
$\begin{array}{cl}
= & C^{12}_2 – 12 \\
= & 72 – 12 \\
= & 60
\end{array}$
III is not true. The number of folds of rotational symmetry of the polygon is $12$.
