XOR operations. You remember operation with A B = AB' + BA'. You remember the commutative law, associative law and also Interesting things about A 0, A I, A A, A A', A B = A C implies B = C, and the application to WiFi. (a) Prove or disprove if A B = C, then A C = B. (b) Prove or disprove if A B = C D, then A C = B D. Here A, B, C, D are all signals of 1 bit equal to 0 or 1. FYI: Try your best to solve as many questions as possible. Grading will be done by curve and top few will get A and A. Try to make sure your accumulated score is at least 40 points for passing