In the circuit below consider only the single faults on wires $a,b,c,$ and $d.$

$($a$)$ Construct a truth table

$($b$)$ Construct a fault table

$($c$)$ Describe a fault detection experiment for the circuit using a minimum set of tests.

$\backslash$table$[[$WXY$],[000],[001],[010],[011],[100],[101],[110],[111]]$

$\backslash$table$[[$WXY$,,,,,,,,,,,,,,],[000,,,,,,,,,,,,,,],[001,,,,,,,,,,,,,,],[010,,,,,,,,,,,,,,],[011,,,,,,,,,,,,,,],[100,,,,,,,,,,,,,,],[101,,,,,,,,,,,,,,],[110,,,,,,,,,,,,,,],[111,,,,,,,,,,,,,,]]$