A cuboid glass container with a square bottom and a side length of 2 decimeters contains 5.6 liters of water. An apple is submerged in the water. The water depth in the measured container is 1.5 decimeters. Find the volume of the apple.
一个长方体玻璃容器，底面是正方形，边长是2分米有5.6升水，将一个苹果浸没在水中，这时量的容器内的水深1.5分米，求苹果体积．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">5.6 / 4</gadget>
<output>1.4</output>

<gadget id="calculator">1.5 - 1.4</gadget>
<output>0.1</output>

<gadget id="calculator">2 * 2 * 0.1</gadget>
<output>0.4</output>

<result>0.4</result>