How many square centimeters of advertising paper is needed to pack the side of a cylindrical can with a bottom diameter of 6 cm and a height of 10 cm.
要包装一个底面直径6厘米，高10厘米的圆柱形易拉罐的侧面，至少需要多少平方厘米的广告纸．
<gadget id="calculator">3.14 * 6 * 10</gadget>
<output>188.4</output>

<result>188.4</result>