When purchase orders are entered into the computer and processed, errors are sometimes found that require special attention to correct them. Special attention is expensive so people would like the percentage of problems to be small. To keep an eye on the problem, people regularly look at a percentage chart, or P chart. For each batch of 300 purchase orders, the percent of errors is recorded. Assuming no standards are given, construct a P chart based on the following data.

Batch Errors Proportion of Errors

1 20 0.067

2 14 0.047

3 12 0.040

4 10 0.033

5 9 0.030

6 8 0.027

7 18 0.060

8 11 0.037

9 11 0.037

10 21 0.070

11 17 0.057

12 18 0.060

13 15 0.050

14 13 0.043

15 17 0.057

16 15 0.050

17 9 0.030

18 13 0.043

19 15 0.050

20 13 0.043

21 14 0.047

22 11 0.037

23 19 0.063

24 20 0.067

25 15 0.050

1) In this chart, the centerline goes along

a)0.0477

b)0.0400

c)0.0401

d)0.0470

2) The upper control limit is

a)0.0000

b)0.0847

c)0.0482

d)0.0556

3) The lower control limiti is

a)0.0108

b)0.0000

c)0.0472

d)0.0398

4) Regarding variability, would you say the process is in control?

a)YES

b)NO

c)The centerline should be around 1/6 above the actual value

d)The average poportion should be checked and properly adjusted

I have to submit this task please help me the answer is one of the option from a to d

Thank You