There is a closed cuboid glass box with a length of 8 cm, a width of 4 cm, and a height of 5 cm, which contains a liquid of 2 cm in height. In order to minimize the occupied area of the cuboid glass box, the box is placed upright, what is the height of the liquid in the box in centimeters.
有一个封闭的长方体玻璃盒，长8厘米，宽4厘米，高5厘米，里面装有2厘米高的液体．为将长方体玻璃盒的占地面积减至最少，现将盒子竖过来放置，这时盒子内液体的高度是多少厘米．
<gadget id="calculator">4 * 5</gadget>
<output>20</output>

<gadget id="calculator">2 / 20</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">8 * 4 * (1/10)</gadget>
<output>16/5 = around 3.2</output>

<result>16/5 = around 3.2</result>