A steel cylinder is 1.8 meters long, has a base radius of 0.4 decimeters, and weighs 7.8 kilograms per cubic decimeter. How many kilograms does this piece of round steel weigh?
一段圆柱体钢长1.8米，底面半径为0.4分米，每立方分米重7.8千克．这段圆钢重多少千克？
<gadget id="calculator">0.4 ** 2</gadget>
<output>0.16</output>

<gadget id="calculator">1.8 * 10</gadget>
<output>18</output>

<gadget id="calculator">3.14 * 0.16 * 18 * 7.8</gadget>
<output>70.53696</output>

<result>70.53696</result>