A cylindrical bucket has a base diameter of 20 cm measured from the inside and a height of 25 cm. What is the volume of this bucket in liters?
一个圆柱形水桶，从里面量得底面直径是20厘米，高25厘米．这个水桶的容积是多少升？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<gadget id="calculator">25 / 1_000</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">3.14 * 100 * (1/40)</gadget>
<output>7.85</output>

<result>7.85</result>