Choose your answer before opening the explanation. This is a learning exercise, not a competency assessment.
DMR's manual gives casing thickness as:
- 3 to 4 cm in one place and 4 to 5 cm in another
- Exactly 2 cm
- 10 cm
- No figure at all
See the answer and why
3 to 4 cm in one place and 4 to 5 cm in another Two figures in one chapter, so the farm sets its own standard.

