If the radius of the base of a cylinder is doubled and the height remains the same, its volume will be multiplied by as many times.
把一个圆柱的底面半径扩大2倍，高不变，它的体积就扩大多少倍．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>