A round bar has a base diameter of 10 cm and a length of 50 cm, what is its lateral area in square centimeters?
一根圆钢的底面直径为10厘米，长为50厘米，它的侧面积是多少平方厘米．
<gadget id="calculator">3.14 * 10 * 50</gadget>
<output>1_570</output>

<result>1_570</result>