For the convenience of irrigation, Shi dared to dig a cylindrical reservoir with a volume of 628 cubic meters on the hill contracted by himself. The diameter of the pool mouth is 20 meters. How deep should it be?
为灌溉方便，施敢在自己承包的山丘上挖一个容积是628立方米的圆柱形蓄水池，池口直径20米，应挖几米深？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<gadget id="calculator">3.14 * 100</gadget>
<output>314</output>

<gadget id="calculator">628 / 314</gadget>
<output>2</output>

<result>2</result>