A manufacturing company tested the processing time for their machine As to process the same digital board. Six samples with 5 machine As per sample were tested. Data recorded in minutes is shown below:

Observation Number	Sample 1	Sample 2	Sample 3	Sample 4	Sample 5	Sample 6
1	15.00	13.80	14.00	13.90	13.90	15.00
2	14.60	14.00	14.10	14.20	13.90	15.70
3	15.10	14.30	14.90	14.80	13.80	14.80
4	14.80	14.60	15.00	13.90	14.00	15.40
5	13.90	15.00	14.70	15.00	14.30	15.00
Sample Mean	14.68	14.34	14.54	14.36	13.98	15.18

a. Using the factor chart for three-sigma control limits for mean chart and range charts (Table 10.3 on page 433) determine the upper and lower limits for mean and range charts, and decide if the process is in control (Do not round intermediate calculations. Round your final answer to three decimal places).

b. Determine if the process is in control on the above control limits.