A cuboid water tank measures 60 cm in length, 50 cm in width, and 45 cm in height from the inside, and the current water depth is 40 cm. There was a stone in the water tank, and the depth of the water after taking out the stone is 30 cm. What is the volume?
一个长方体水缸，从里面量长60厘米，宽50厘米，高45厘米，现水深40厘米，水缸里原有一块石头，把石头拿出来后水的深度为30厘米，问这块石头的体积是多少？
<gadget id="calculator">40 - 30</gadget>
<output>10</output>

<gadget id="calculator">60 * 50 * 10</gadget>
<output>30_000</output>

<result>30_000</result>