For Problem 15-16, develop upper and lower con-trol limits for the range. Do these samples indicate that the process is in control?
In Problem 15-16, Colonel Electric is a large company that produces lightbulbs and other electrical products. One particular lightbulb is supposed to have an average life of about 1,000 hours before it burns out. Periodically the company will test 5 of these and measure the average time before these burn out. The following table gives the results of 10 suchsamples:

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SAMPLE No. 1 RI No. RI No. SAMPLE SAMPLIE 63.5 20 10 63.5 13 18 63.6 1.8 2 63.6 10 63.3 18 19 63.8 1.3 3 63.7 1.7 63.2 .0 20 63.5 1.6 4 63.9 0.9 3 63.6 18 2 63.9 1.0 5 634 14 63.3 15 22 63.2 1.8 6 63.0 16 15 634 17 23 63.3 1.7 7 63.2 18 6 63.4 4 24 64.0 2.0 8 633 3 7 63.5 25 63.4 1.5 9 63.7 1.6 SAMPLE23 456 7 8 9 10 Mean 979 1087 1080 934 1072 1007 952 986 1063 958 Range 0 94 57 65 135 134 10 98 145 84