You make a measurement using a digital voltmeter that provides four digits $($no specifications from the manufacturer$)$ and record an average value of $15\mathrm{.}82V.$ Report the measurement $($including uncertainty$)$ for each of the following scenarios:

a$)$ The value of $15\mathrm{.}82V$ is stable across the entire measuring period.

b$)$ The value oscillates randomly from $15\mathrm{.}75V$ to $15\mathrm{.}89V$ with all values appearing equally likely.

c$)$ The value oscillates randomly from $15\mathrm{.}75V$ to $15\mathrm{.}89V$ with central values appearing more likely than the edge values.