1. Four circles of radius 1cm are drawn with their centres at the four vertices of a square with side length 1cm. The area, in square centimetres, of the region overlapped by all four circles is?
2. Let f(x)=(x+6)/x and fn(x)=f(f(...(f(x)...))be the n-fold composite of f. For example, f2(x)=/. Let S be the complete set of real solutions of the equation fn(x)=x. The number of the elements in S is?
(A)2 (B)2n (C)2^n (D)1 (E)infinite
有点难，谢谢了！最好有过程~
