Logic Gates

$15.$ Give the Logic symbol, Boolean expression and Truth Table for a $2-$input $($A $\backslash$& B$)$ AND gate.

Expression $-$

Truth $-$

Symbol:

$16.$ Given below is a timed series of the status of two input signals $\backslash ($ A $\backslash )$ and $\backslash ($ B $\backslash ).$ Fill in the corresponding outputs for $\backslash ((\backslash$mathrm$\{$A$\}+\backslash$mathrm$\{$B$\})\backslash )$ and $\backslash (\backslash$operatorname$\{$NOR$\}(\backslash$mathrm$\{$A$\},\backslash$mathrm$\{$B$\})\backslash )$

$17.$The output of a logic signal may be stopped by using a buffer$/$driver$.$

$18.$Show the meaning of an inverter bubble in an inverter buffer$/$driver and explain what would happen if the bubble were not present.