A sample has mean $25$ and standard deviation $8.$

Part $1$ of $2$

$($a$)$ What value is $0\mathrm{.}5$ standard deviations below the mean?

The value that is $0\mathrm{.}5$ standard deviations below the mean is $21.$

Part: $\frac{1}{2}$

Part $2$ of $2$

$($b$)$ What values are $3$ standard deviations from the mean?

The values that are $3$ standard deviations from the mean are and