How many square meters of glass is needed to make a cube glass water tank (without cover) with an edge length of 0.4m?
制做一个棱长0.4m正方体玻璃水槽(无盖)，至少需要玻璃多少平方米？
<gadget id="calculator">0.4 * 0.4 * 5</gadget>
<output>0.8</output>

<result>0.8</result>