Does anyone know how to do these 3 questions? Mainly 8

Question 8: Let A, B, and C be sets. Use a set identities to show that a)A-B=B-A b) (An B)u (An B) A c)A-(B-C)=(A-B) U (A-C) Question 9: Can you conclude that A-B, if A, B, and C are sets, such that: a) AUC BUC? c)(AUC#BUC) and (AnC BnC)? Question 10: Find U A and n1 Ai, if for every positive integer i a) Ai = {-1,-1 + 1, ,-1, 0, 1, , 1-1, i} b) Ai = {-1,1} c) A -i,i], that is, the set of real numbers x with -isx si d) A,), that is, the set of real numbers x with x2-i