Cold working produces the following effects:
1. Stresses are set up in the metal
2. Grain structure gets distorted
3. Strength and hardness of the metal are decreased
4. Surface finish is reduced
Which of these statements are correct?
(a) 1 and 2 (b) 1, 2 and 3
(c) 3 and 4 (d) 1 and 4