Answer
$ a.\quad$ acceptable.
$ b.\quad$not acceptable.
Work Step by Step
a.
Does $x=108$ satisfy
$|x-110|\leq 5\quad ?$
$|108-110|=|-2|=2.$
Since $2\leq 5$, the voltage of 108 Volts is acceptable.
b.
Does $x=104$ satisfy
$|x-110|\leq 5\quad ?$
$|104-110|=|-6|=6.$
So, the voltage of 104 Volts is not acceptable.