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PRACTICE EXAM 3 PROBLEM 3 SOLUTION 1250 F 14 EX: Using only 2-input logic gates, i.e., AND, NAND, OR, NOR, XOR, or XNOR, design a logic circuit with the following truth table: A 0 0 0 0 1 1 1 1 SOL'N: Inputs B 0 0 1 1 0 0 1 1 C 0 1 0 1 0 1 0 1 Output Y 0 1 0 1 1 1 0 1 The output equals C except for A=1, B=0, and C=1, in which case the output should also be 1. Y = C + A⋅B (1) Note that we do not need to include C in the second term, since we want Y=1 whether B=0 or B=1. To invert B, we use a NAND gate with inputs tied together.