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The BCD/DEC decoder shown in figure (a) is examined with a logic analyzer and the results are shown in the waveforms in figure (b). What, if anything, is wrong with the circuit?

The "2" output is shorted to Vcc.
The A1 input is internally open.
The A1 input node is internally stuck LOW.
Nothing is wrong with the circuit.

Correct Answer: The A1 input node is internally stuck LOW.

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