$1.$ Develop $3$ sigma level process control charts for monitoring weight of firewood in bags. An inspector performed sampling over $4$ weeks of time frame. Each time, $4$ observations were made as below. Calculate and show values for UCL, CL$,$ and LCL using the factors provided in below table $($do not calculate these values using the raw data$).$ Draw variable control charts $($mean and range$).$ Discuss your conclusion. You can draw using Excel or hand draw and scan.

week $1$ week $2$ week $3$ week $4$

$20282030$

$24302820$

$22212624$

$26242626$