A block of iron is immersed in a cuboid container with a base area of 20 square centimeters and a height of 5 centimeters. After taking out the iron block, the water level dropped by 3 cm. Find the volume of this iron block.
在一个底面积为20平方厘米，高为5厘米的长方体容器中，浸没着一个铁块．取出铁块后，水面下降了3厘米．求这个铁块的体积．
<gadget id="calculator">20 * 3</gadget>
<output>60</output>

<result>60</result>