concave lens practical

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10:02

6:42

17:36

7:25

7:06

18:13

3:16

23:17

6:06

6:30

20:15

5:50

20:51

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7:20

6:35

2:05

34:01

26:02

4:52

00:55

28:39

4:23

00:49

3:49

9:51

4:36

9:53

2:17

13:56

10:51

24:32

2:11

13:19

10:55

7:37

10:14

1:15

2:49

7:12

1:14

27:39

1:00

23:22

13:00

3:06

8:54

8:14

8:27

13:47

56:04

00:59

5:27

7:49

19:55

2:09

21:57

18:26