A piece of cuboid steel with a length of 20 decimeters and a cross-sectional area of 20dm**2, if each cubic decimeter of steel weighs 7.8 kilograms, what is the total weight of the steel in kilograms?
一块长20分米横截面的面积是20dm**2的长方体钢材，如果每立方分米的钢材重7.8千克，这个钢材共重多少千克．
<gadget id="calculator">20 * 20 * 7.8</gadget>
<output>3_120</output>

<result>3_120</result>