refraction explained step by step

5:29

2:46

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2:40

6:49

3:16

14:02

7:28

14:49

15:10

13:30

3:05

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14:45

14:39

7:42

10:30

2:55

2:56

8:51

10:40

3:32

4:25

9:27

6:44

12:55

10:15

3:18

3:18

3:29

3:09

3:07

2:59

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3:13

2:54

2:27

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2:45

4:20