Roll a piece of rectangular white paper with a length of 30 cm and a width of 18 cm into a cylinder. What is the lateral area of the cylinder in square centimeters?
将一张长30厘米，宽18厘米的长方形白纸卷成一个圆柱，这个圆柱的侧面积是多少平方厘米．
<gadget id="calculator">30 * 18</gadget>
<output>540</output>

<result>540</result>