The school wants to dig a 4.5m long, 3m wide, and 1.5m deep reservoir in a corner of the playground. How much earth does it need to dig?
学校要在操场一角挖一个长4.5m，宽3m，深1.5m的蓄水池，需要挖多少方土？
<gadget id="calculator">4.5 * 3 * 1.5</gadget>
<output>20.25</output>

<result>20.25</result>