A cylinder has a base radius of 2.5 cm and a height of 8 cm, what is its lateral area?
一个圆柱的底面半径是2.5cm，高是8cm，它的侧面积是多少．
<gadget id="calculator">2 * 3.14 * 2.5 * 8</gadget>
<output>125.6</output>

<result>125.6</result>