A pizza delivery service has an average delivery time of $26\mathrm{.}2$ minutes and a standard deviation of $1\mathrm{.}35$ minutes. The nominal value is $25$ minutes with a tolerance of $5$ minutes. Is the delivery process capable at the $3-$sigma level? Is the variability too high?

Hint: Process is not capable because $Cpk<mn\; id="EditorElement\_732689">1</mn>$; process variability not too high as $Cp>1$