Q$2$ Consider an AND$-$OR circuit in Fig$\mathrm{.}2-1.$ The propagation delay through each gate is $t_{pd}.[25]$

$($a$)$ Suppose the input signals are shown in Fig$\mathrm{.}2-2.$ Complete the timing diagram for $F1,F2,F3$ and $F.$

$[8]$

$($b$)$ If you observe the waveform of the output signal $F$ you may find some narrow pulses.

i$)$ Give reasons why this might be the case.

$[2]$

ii$)$ How might the problem be solved?

$[2]$

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