If the base area of a cylinder remains the same, if the height increases by 2 cm, the surface area will increase by 62.8 cm2. What is the area of the base of this cylinder in square centimeters?
一个圆柱，它的底面积不变，如果高增加2厘米，表面积就增加62.8平方厘米．这个圆柱的底面积是多少平方厘米．
<gadget id="calculator">62.8 / 2 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<result>78.5</result>