What is the volume of a cylinder obtained by expanding its sides to obtain a square with a base radius of 3 cm?
一个圆柱侧面展开得到一个正方形，底面半径3厘米，体积是多少．
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

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

<gadget id="calculator">28.26 * 18.84</gadget>
<output>532.4184</output>

<result>532.4184</result>