Question 21

The threaded portion of a 1 1/4-inch steel gas pipe has approximately 11 threads cut.

A 1 1/4-inch steel gas pipe typically has around 11 threads cut into its threaded portion, making this the most accurate choice based on standard practices in plumbing and gas fitting.

A) 10

Option A is incorrect because a 1 1/4-inch steel gas pipe does not have as few as 10 threads. Generally, the threading on such pipes is standardized, and a count of 10 would be below the typical number found.

B) 11

Option B is correct as it aligns with the standard threading specification for a 1 1/4-inch steel gas pipe, which typically features approximately 11 threads cut. This count is consistent with industry norms.

C) 12

Option C is incorrect because while 12 threads may seem plausible, it exceeds the standard count for a 1 1/4-inch steel gas pipe. Most specifications indicate a lower number, making 12 an inaccurate choice.

D) 13

Option D is also incorrect as it suggests an even higher number of threads than is standard for this type of pipe. The typical threading does not reach 13 threads for a 1 1/4-inch steel gas pipe.

Conclusion

The correct answer is 11 threads, as this figure is based on established standards for the threading of 1 1/4-inch steel gas pipes. All other options fail to accurately reflect the typical threading count, demonstrating a lack of alignment with industry standards. Thus, Option B is definitively the right choice.