A cylindrical pool is measured from the inside. The circumference of the bottom is 31.4 meters and the depth is 2 meters. What is its volume in cubic meters?
一个圆柱形水池从里面量，底面周长是31.4米，深2米，他的容积是多少立方米？
<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 2</gadget>
<output>157</output>

<result>157</result>