85. The only function of a NOT gate is to
A. stop a signal
B. recomplement a signal
C. invert an input signal
D. act as a universal gate

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86. A NOR gate is ON only when all its inputs are
A. ON
B. positive
C. high
D. OFF

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87. For getting an output from an XNOR gate, its both inputs must be``
A. high
B. low
C. at the same logic level
D. at the opposite logic levels

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88. In a certain 2-input logic gate, when A = 0, B = 0, then C = 1 and when A = 0, B = 1, then again C = 1. It must be gate.
A. XOR
B.AND
C. NAND
D. NOR

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89. The logic symbol shown in Fig. 7.1 represents
A. single-output AND gate
B. NAND gate
C. NAND gate used as NOT gate
D.

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90. A half-adder can be constructed from
A. two XNOR gates only
B. one XOR and one OR gate with their outputs connected in parallel
C. one XOR and one OR gate with their inputs connected in parallel
D. one XOR gate and one AND gate

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91. The digital equivalent of an electric series circuit is the gate.
A. NOR
B. NAND
C. OR
D. AND

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