If the sides of a cylinder are unfolded to obtain a square with a side length of 6.28 cm, what is the area of the base of the cylinder in square centimeters?
一个圆柱的侧面展开后得到一个边长是6.28厘米的正方形，这个圆柱的底面积是多少平方厘米．
<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">6.28 / 6.28</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<result>3.14</result>