Question: ) Assume that a demerit chart is to be produced, and the numbers of demerits assigned to each of three types of nonconformities are 5, 3, and 2, respectively. The data for 20 inspection units are as follows, where , , and denote the number of nonconformities of each of the three types.

Unit #				Unit #
1	3	5	2	11	2	3	1
2	2	4	5	12	4	4	2
3	1	2	3	13	3	1	0
4	2	4	1	14	2	0	1
5	3	2	3	15	3	2	3
6	4	3	2	16	4	1	2
7	2	1	2	17	5	3	4
8	2	0	3	18	2	3	6
9	3	2	2	19	1	2	4
10	0	3	1	20	3	1	1

a. Construct the D-chart (that corresponds to c-chart) and test for control.

b. Would three separate c-charts have indicated statistical control?