If a cylinder with a base area of 15.7 square centimeters is cut into two cylinders of the same size, how many square centimeters will the surface area increase?
将一个底面积是15.7平方厘米的圆柱，切成两个同样大小的圆柱，表面积增加了多少平方厘米．
<gadget id="calculator">15.7 * 2</gadget>
<output>31.4</output>

<result>31.4</result>