Combine two identical half cylinders to form a cylinder with a base radius of 3 cm and a reduction in surface area of 72 cm2. What is the lateral area of this cylinder in square centimetres?
把两个完全一样的半个圆柱合并成一个圆柱，底面半径是3厘米，表面积减少72平方厘米．现在这个圆柱的侧面积是多少平方厘米？
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">72 / 2 / 6</gadget>
<output>6</output>

<gadget id="calculator">3.14 * 3 * 2 * 6</gadget>
<output>113.04</output>

<result>113.04</result>