The fill size for a small bag of peanuts distributed by a popular airline is 50 grams. The producer ...

The fill size for a small bag of peanuts distributed by a popular airline is 50 grams. The producer wishes to set up a set of control charts for this process and collects the data shown in the table.
 
  What are the upper and lower control limits of their X-bar chart?
 
  Sample Item 1 Item 2 Item 3 Item 4 Sum
  1 54.5 54.3 53.8 50.4 213.0
  2 50.6 53.5 53.2 54.9 212.3
  3 51.1 54.3 50.4 50.7 206.6
  4 52.7 52.1 51.3 51.0 207.2
  5 51.7 51.2 54.7 54.3 211.8
  6 51.1 51.5 54.7 50.4 207.7
  7 54.0 52.3 54.7 51.4 212.4
  8 53.2 50.4 53.4 51.4 208.4
  9 51.9 50.2 50.2 52.9 205.1
 
  A) 54.84, 49.85
  B) 54.41, 50.32
  C) 53.87, 50.78
  D) 53.51, 51.18