A cylindrical wooden barrel with a base diameter of 16 cm and a height of 2 decimeters, what is its lateral area?
一个圆柱木桶，底面直径16厘米，高2分米，它的侧面积是多少？
<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">3.14 * 16 * 20</gadget>
<output>1_004.8</output>

<result>1_004.8</result>