After the side of a cylinder is unfolded, it is exactly a square with a side length of 31.4 cm. What is the side area of this cylinder in square centimeters?
一个圆柱的侧面展开后，正好是一个边长为31.4厘米的正方形，这个圆柱的侧面积是多少平方厘米．
<gadget id="calculator">31.4 * 31.4</gadget>
<output>985.96</output>

<result>985.96</result>