If the pitch of the propeller is 21.5 feet, and the revolutions per day are 96,666, calculate the day's run allowing 9% negative slip.

Correct Answer: Option C — 372.6 miles

Theoretical distance is revolutions per day multiplied by propeller pitch, divided by feet per nautical mile (6080). Applying a 9% negative slip means multiplying the theoretical run by 1.09, resulting in a true day's run of 372.6 miles.