If the sides of a cylinder are expanded to form a square, if the radius of the base of the cylinder is 3 cm, what is its volume?
一个圆柱的侧面展开后是一个正方形，如果这个圆柱的底面半径是3cm，它的体积是多少．
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 3 * 2</gadget>
<output>18.84</output>

<gadget id="calculator">3.14 * 9 * 18.84</gadget>
<output>532.4184</output>

<result>532.4184</result>