Dig a cylindrical cistern with a bottom radius of 5 meters and a depth of 4 meters. How many cubic meters of water can this cistern hold?
挖一个圆柱形蓄水池，底面半径是5米，深是4米，这个蓄水池可蓄水多少立方米？
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 4</gadget>
<output>314</output>

<result>314</result>