Function & Set & Possibility question (Solved)

For set A={1, 2, 3, 4, 5}, how many functions f  from set A to set A satisfy the following conditions?

(A) n({f(x)|x E A}) = 3
(B) composite function f*f's range have 2 elements.

a) 900 b) 1440 c) 1080 d) 1620 e) 1200

(I'm not English user, so translation might be rough. I want to know how to solve this problem.)

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