A rectangular parallelepiped tank is 10cm long and 4cm wide, filled with 8cm deep water, put a potato, the potato is completely submerged by the water, and the water depth rises to 10cm. What is the volume of this potato?
一个长方体水缸，长是10cm，宽是4cm，里面装有8cm深的水，放进一个土豆，这个土豆被水完全淹没，这时水深上升到10cm．这个土豆的体积是多少？
<gadget id="calculator">10 - 8</gadget>
<output>2</output>

<gadget id="calculator">10 * 4 * 2</gadget>
<output>80</output>

<result>80</result>