A cube glass jar with a side length of 4dm. After filling it with water, pour all the water into a tank with a bottom area of 20dm**2. What is the height of the water surface in the tank?
一个正方体玻璃缸，棱长为4dm，用它装满水后，再把水全部倒入一个底面积为20dm**2的水槽中，水槽里水面的高度是多少分米？
<gadget id="calculator">4 / 20</gadget>
<output>1/5 = around 0.2</output>

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

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