A cube-shaped glass fish tank with a side length of 3 decimeters, how many square decimeters of glass is needed to make this fish tank (there is no cover on the top of the fish tank)
一个正方体形状的玻璃鱼缸，棱长3分米，制作这个鱼缸时至少需要玻璃多少平方分米(鱼缸的上面没有盖)
<gadget id="calculator">3 * 3 * 5</gadget>
<output>45</output>

<result>45</result>