A glass fish tank is in the shape of a cube with sides 3dm long. What is the minimum square decimeter of glass needed to make this fish tank?
一个玻璃鱼缸的形状是正方体，棱长3dm．制作这个鱼缸时至少需要玻璃多少平方分米？
<gadget id="calculator">3 * 3 * 5</gadget>
<output>45</output>

<result>45</result>