rectangular parallelepiped glass container whose bottom is 2dm in length and width contains 5.6 liters of water, and then an apple is put into the water. At this time, the water depth in the container is 1.5dm. What is the volume of the apple in cubic decimeters? (Glass thickness is ignored)
一个底面长和宽都是2dm的长方体玻璃容器，里面装有5.6升水，再将一个苹果放入水中，这时容器内的水深1.5dm，这个苹果的体积是多少立方分米？(玻璃厚度忽略不计)
<gadget id="calculator">2 * 2 * 1.5</gadget>
<output>6</output>

<gadget id="calculator">6 - 5.6</gadget>
<output>0.4</output>

<result>0.4</result>