The height of a cylinder is 12.56 centimeters, and the sides are expanded to form a square. What is the area of the base of this cylinder in square centimeters?
一个圆柱的高是12.56厘米，侧面展开后是一个正方形．这个圆柱的底面积是多少平方厘米．
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<result>12.56</result>