1. Realize the following functions using AND and OR gates. Assume that there are no restrictions on the number of gates which can be cascaded and minimize the number of gates inputs. a. WXY' + WX'Y + XY'Z b. DB + AE'C' + BE'C' + A'D'E' + DA 2. Realize Z = CDA + AB + CEFA using only two-input NOR gates. Use as few gates as possible. 3. Find a minimum two-level NAND-NAND circuit to realize: a. ABC + DAB' + A'B'C + A'BC b. R+R'ST c. A' + BCD' + AB 4. Using AND and OR gates, find a minimum two-level circuit to realize: a. F = B'D' + BD' + B'CD + ABC + ABC'D b. F = AB'D' + A'B + A'C + CD