回複：no - ANSWER to this question is yes, (4.60338811)

Hai,how did you get this question? I think you transfer from a phy or math guestion. The duck can't be free if fox is smart enough. 4.6003388 is the Min of function F(x)=(Pi+arccos(x))/squat(1-x^2),x=.22.In fact,the fox can change direction.