A swale must fall 2 percent over a 50-foot run. What vertical fall is required?
Correct Answer
A) 1 foot.
Two percent of 50 feet is 1 foot of fall.
Why This Is the Correct Answer
Two percent of 50 feet is 1 foot of fall.
Why the Other Options Are Wrong
Option B: 2 feet.
2 feet. is above the supported result for earthwork grading calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option C: 4 inches.
4 inches. is above the supported result for earthwork grading calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 10 inches.
10 inches. is above the supported result for earthwork grading calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Measure to percent, adjust for feet, then let Checking Rough set the finish line.
Reference Hint
Study anchor (closed-book): memorize Earthwork grading calculation from California Building Code, California Code of Regulations Title 24. / Title 24 California Building Code drainage and grading concepts; know the rule or calculation trigger without relying on exam-room lookup.
More Class B Trade Questions
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