Final answer:
A furlong is an old measure of distance defined as the distance a horse can pull a plow without resting, approximately 220 yards. It is used in both the Imperial and US customary systems of measurement.
Step-by-step explanation:
The measure that is defined as the 220-yard distance a horse can pull a plow without resting is known as a furlong.
This term is used in both the Imperial and US customary systems of measurement and is commonly associated with horse racing. The reference provided of driving a car at exactly 50 mph.
Applying the brakes until it stops and recording the distance, is an unrelated example and does not apply to the concept of a furlong.
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