stone is placed in a glass fish tank with a length of 50 cm, a width of 40 cm, and a height of 30 cm, and the stone sinks to the bottom of the water. As a result, the water level rose by 3.5 cm. What is the volume of this stone?
在一个长50厘米，宽40厘米，高30厘米的玻璃鱼缸里放入一块石头，石头沉入水底．结果水面上升了3.5厘米．这块石头的体积是多少？
<gadget id="calculator">50 * 40 * 3.5</gadget>
<output>7_000</output>

<result>7_000</result>