A cylinder of steel is 2 meters long and its cross-sectional diameter is 4 cm. If the steel weighs 7.8 kg per cubic centimeter, how many kilograms does this steel weigh? (The result is rounded to one decimal place)
一根圆柱体钢材长2米，它的横截面直径是4厘米，如果每立方厘米钢重7.8千克，这根钢材大约重多少千克？(结果保留一位小数)
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">2 * 100</gadget>
<output>200</output>

<gadget id="calculator">3.14 * 4 * 200 * 7.8</gadget>
<output>19_593.6</output>

<result>19_593.6</result>