If the height of a cylinder is truncated by 2 centimeters, the surface area will be reduced by 12.56 square centimeters. What is the diameter of the base of the cylinder in centimeters?
一个圆柱的高截去2厘米，表面积就减少12.56平方厘米，这个圆柱的底面直径是多少厘米．
<gadget id="calculator">12.56 / 2 / 3.14</gadget>
<output>2</output>

<result>2</result>