The following data is obtained from a process control chart

Sample #

# defects

$1$

$23$

$2$

$34$

$3$

$15$

$4$

$30$

$5$

$25$

$6$

$22$

$7$

$18$

If the number of observations for each sample is $150$ units, what is the $3-$sigma upper control limit of the process?

Group of answer choices