A cylindrical glass has a measured inner diameter of 10 cm and a depth of 16 cm of liquid medicine inside, accounting for exactly 80% of the capacity of the glass. If it is filled with liquid medicine, how many milliliters should it be.
一个圆柱形的玻璃杯，测得内直径是10厘米，内装药水深度有16厘米，正好占杯内容量的80%．如果装满药水，应是多少毫升．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

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

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">16 / (4/5)</gadget>
<output>20</output>

<gadget id="calculator">78.5 * 20</gadget>
<output>1_570</output>

<result>1_570</result>