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Digital Logic — question 1 of 10

Write a real answer. It is graded against the question's rubric, and the mastery movement is computed by the same engine the product uses. Scoring here is deterministic rather than model-written, so this page costs nothing to run and nothing is saved. In a track built from your own posting, the same rubric is graded by the model, which is what produces feedback about your reasoning rather than about coverage.

This is a first-pass check on whether a candidate understands combinational logic as delay-laden circuitry rather than an instantaneous truth table.

You build a 4-to-1 multiplexer out of three 2-to-1 muxes (two feeding a third), and you use it to select between four sensor signals based on a 2-bit select code. When you scope the output while the select lines are changing between certain codes, you occasionally see a very brief unwanted pulse (a glitch) on the output even though the correct value settles a few nanoseconds later. Explain why this glitch appears and whether it matters for your application.

How sure are you?

Being confidently wrong costs more mastery than admitting a guess — that is deliberate, and it is how misconceptions get found.

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