A cylinder of steel is 2 meters long, the cross-sectional diameter is 4 cm, and the steel weighs 7.8 grams per cubic centimeter. How many kilograms does this steel weigh? (keep one decimal place)
一根圆柱体钢材长2米，横截面直径是4厘米，每立方厘米钢重7.8克，这根钢材约重多少千克？(保留一位小数)
<result>19.5936</result>