Sample size

is $9,$ mean of the sample means

is $12,$ mean of the sample ranges

is $4,$ and population standard deviation is not known. Calculate the

and

of the mean chart for this process, by using $3-$sigma

$.$

n A$2$ D$3$ D$4$

$21\mathrm{.}8800\mathrm{.}0003\mathrm{.}267$

$31\mathrm{.}0230\mathrm{.}0002\mathrm{.}575$

$40\mathrm{.}7290\mathrm{.}0002\mathrm{.}282$

$50\mathrm{.}5770\mathrm{.}0002\mathrm{.}114$

$60\mathrm{.}4830\mathrm{.}0002\mathrm{.}004$

$70\mathrm{.}4190\mathrm{.}0761\mathrm{.}924$

$80\mathrm{.}3730\mathrm{.}1361\mathrm{.}864$

$90\mathrm{.}3370\mathrm{.}1841\mathrm{.}816$

$100\mathrm{.}3080\mathrm{.}2231\mathrm{.}777$

Group of answer choices

UCL$=11\mathrm{.}1,$ LCL$=12\mathrm{.}9$

UCL $=10\mathrm{.}65,$ LCL $=13\mathrm{.}35$

Cannot be calculated

UCL$=12\mathrm{.}9,$ LCL$=11\mathrm{.}1$

UCL $=13\mathrm{.}35,$ LCL $=10\mathrm{.}65$