A tire manufacturer periodically tests its tires for tread wear under simulated road conditions. To study and control its manufacturing processes, the company uses -charts. The data has been collected below. Perform the required analysis to answer the questions below.

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DATA	1	2	3	4	5		Range	Average	LCLx-bar	Center	UCLx-bar
1	22	45	47	29	30
2	25	21	40	46	33
3	46	20	23	18	20
4	22	29	21	23	31
5	37	44	26	30	46
6	22	39	28	26	41
7	31	50	31	37	27
8	38	48	46	16	49
9	24	18	33	49	29
10	22	28	29	19	16
11	42	39	18	48	20
12	34	26	34	33	21
13	49	35	50	24	50
14	47	27	33	31	31
15	25	31	27	26	32
16	45	19	34	45	29
17	41	35	23	19	23
18	45	35	16	16	32
19	19	22	22	37	47
20	36	44	21	39	19
21	42	20	18	27	35
22	22	28	16	42	35
23	39	17	38	26	30
24	26	38	19	24	17
25	19	31	16	32	48
26	29	41	37	39	18
27	27	26	30	47	47
28	17	21	41	38	22
29	49	45	37	22	26
30	39	29	19	20	34
	Control Chart Factors										Number of samples
n	A2	D3	D4	d2	A3	B3	B4				Sample size
2	1.880	0.000	3.267	1.128	2.659	0.000	3.267
3	1.023	0.000	2.574	1.693	1.954	0.000	2.568				Grand Average
4	0.729	0.000	2.282	2.059	1.628	0.000	2.266				Average Range
5	0.577	0.000	2.114	2.326	1.427	0.000	2.089
6	0.483	0.000	2.004	2.534	1.287	0.030	1.970				Control Chart Factors (see cell A36)
7	0.419	0.076	1.924	2.704	1.182	0.118	1.882				A2
8	0.373	0.136	1.864	2.847	1.099	0.185	1.815
9	0.337	0.184	1.816	2.970	1.032	0.239	1.761
10	0.308	0.223	1.777	3.078	0.975	0.284	1.716

Questions

1. What is the number of samples? Round your answer to the nearest whole number.

2. What is the sample size? Round your answer to the nearest whole number.

3. What is the overall mean? Round your answer to three decimal places.

4. What is the average range? Round your answer to three decimal places.

5. What is the value of A2 Control Chart Factor? Round your answer to three decimal places.

6. What is the lower control limit for the -chart? Round your answer to three decimal places.

7. What is the value that specifies the center line for the -chart? Round your answer to three decimal places.

8. What is the upper control limit for the -chart? Round your answer to three decimal places.