Draw the largest circle in a square with side length 8 cm. What is the area of the circle in the area of the square?
在一个边长为8厘米的正方形内画一个最大的圆，圆的面积占正方形面积的多少．
<gadget id="calculator">78.5 / 100</gadget>
<output>0.785</output>

<result>0.785</result>