A cylinder is formed by a piece of rectangular paper with a length of 12 cm and a width of 6 cm. What is the lateral area of the cylinder?
用一张长12cm宽6cm的长方形纸围成一个圆柱，这个圆柱的侧面积是多少．
<gadget id="calculator">12 * 6</gadget>
<output>72</output>

<result>72</result>