Operations. i got this question wrong and need help figuring out the correct answer. thank you.

two images are attached!!

A quality analyst wants to construct a sample mean chart for controlling a packaging process. Weight Day Package 1 Package 2 Package 3 Package 4 Monday 23 22 23 24 Tuesday 23 21 19 21 Wednesday 20 19 20 21 Thursday 18 19 20 19 Friday 18 20 22 20 What are the UCL and LCL limits? Is the process in control? Can not calculate the control limits UCL (x bar) - 20.6 +0.729 (2.8) = 22.64 LCL (x bar) - 20.6-0.729 (2.8) - 18.55 process is in control. Tuesday 23 21 19 21 Wednesday 20 19 20 21 Thursday 18 19 20 19 Friday 18 20 22 20 What are the UCL and LCL limits? Is the process in control? Can not calculate the control limits O UCL (x bar) = 20.6 +0.729 (2.8) = 22.64 LCL (x bar) - 20.6-0.729 (2.8) = 18.55 process is in control. UCL (x bar) = 20.6 +0.729 (4.25) = 23.69 LCL (x bar) = 20.6-0.729 (4.25) = 17.50 process is not in control. UCL (x bar) - 20.6 +0.577 (4.25) = 23.05 LCL (x bar) - 20.6-0.577 (4.25) - 18.14 process is not in control