A cuboid steel is 2 meters long and has a cross-sectional area of 0.02 square meters. It is known that the steel weighs 7.8 tons per cubic meter. How many tons does this piece of steel weigh?
一根长方体钢材，长2米，横截面面积是0.02平方米，已知每立方米钢材重7.8吨．这根钢材重多少吨？
<gadget id="calculator">2 * 0.02 * 7.8</gadget>
<output>0.312</output>

<result>0.312</result>