Question

which of the following pipe schedules would be listed as standard?
80
20
10
40
question 4
when welding downhill, the travel speed is typically:

Explanation:

In pipe scheduling, Schedule 40 is a widely recognized standard pipe schedule for many applications, especially for common fluid - carrying pipes in various engineering and industrial contexts. Schedules 10, 20, and 80 have different use cases (Schedule 10 is thin - walled, Schedule 20 is also thinner - walled compared to 40, and Schedule 80 is thicker - walled for higher - pressure applications), but Schedule 40 is considered the standard for general - purpose piping.

Answer:

D. 40 (assuming the options are labeled as A. 80, B. 20, C. 10, D. 40; if the original options have different labels, adjust accordingly based on the actual option numbering for 40)