Pour 250 ml of milk into a cylindrical cup with a height of 20 cm. At this time, the height of the milk is 10 cm. What is the volume of the cup?
把250毫升的牛奶倒入一个高是20厘米的圆柱形杯子里，这时牛奶高度是10厘米，这个杯子的容积是多少．
<gadget id="calculator">250 / 10</gadget>
<output>25</output>

<gadget id="calculator">25 * 20</gadget>
<output>500</output>

<result>500</result>