A square fish tank without a cover has a side length of 3 decimeters. How many square decimeters of glass are needed to make such a fish tank?
一个无盖正方体鱼缸棱长3分米，做一个这样的鱼缸，需要多少平方分米的玻璃？
<gadget id="calculator">3 * 3 * 5</gadget>
<output>45</output>

<result>45</result>