day number	Plant 1	Plant 2	Plant 3	Plant 4
1	4	2	5	3
2	3	4	4	3
3	5	5	5	3
4	3	4	4	4
5	3	2	4	3
6	2	4	3	4
7	5	1	5	3
8	3	3	1	5
9	4	5	2	5
10	5	3	5	5
11	8	5	3	5
12	5	4	3	5
13	4	2	4	5
14	8	4	2	5
15	1	1	2	4
16	3	3	4	3
17	4	2	1	3
18	3	3	3	4
19	2	5	3	3
20	5	4	4	5
21	5	5	5	4
22	2	4	3	3
23	5	5	1	3
24	1	3	2	4
25	9	1	1	2
26	4	3	1	3
27	5	2	2	5
28	7	4	3	3
29	5	5	1	5
30	3	3	4	4
31	4	5	1	4
32	4	4	3	4
33	5	3	3	5
34	4	5	4	6
35	7	3	3	3
36	5	4	2	1
37	4	5	4	5
38	3	3	4	4
39	3	2	2	3
40	5	2	3	3
41	4	1	4	5
42	7	3	5	4
43	6	2	1	3
44	5	4	4	2
45	3	5	3	4
46	5	5	4	4
47	5	5	3	5
48	6	5	4	4
49	9	5	3	1
50	7	5	4	4

This data shows the number of employees' injuries reported in the first 50 days after a new device training session in each of the 4 production Plants of a certain company across the world.

a) Assuming significance level of 0.05, is there any significant difference in the injuries reported between these 4 Plants?

b) The manager is particully concerned about the results from Palnt 1 compared to plant 3. Is there evidence that the injury level at this Plant is significantly different from that of Plant 3?