Use the following data to answer questions 17-18.

An assembly line pouring cereal into boxes pulls samples once an hour. In the chart below is the summary of five boxes that are sampled each hour, including the mean weight of each sample and the range between the heaviest and lightest box of the sample. The table shows the results for a 10 hour period. All weights are recorded in ounces.

Hour	Mean weight	Range	Hour	Mean weight	Range
1	19.2	0.13	6	18.5	0.01
2	18.3	0.08	7	18.6	0.12
3	18.3	0.05	8	18.0	0.09
4	18.9	0.07	9	18.5	0.11
5	18.9	0.06	10	18.5	0.08

17. What is the LCL and UCL of the control chart?

a. 18.52 and 18.62

b. 18.08 and 18.57

c. 18.95 and 19.09

d. 18.91 and 19.05

18. What is the LCL of the range control chart

a. 0.17

b. 0.08

c. 0.01

d. 0.00