A cylindrical reservoir with a diameter of 20 meters and a depth of 2 meters. What is the volume of this reservoir?
一个圆柱形蓄水池，直径20米，深2米．这个蓄水池的体积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3.14 * 100 * 2</gadget>
<output>628</output>

<result>628</result>