Applying the brakes repeatedly on a downgrade to reduce speed 5 mph below your target is called ________.

If your safe speed is 40 mph, you should apply the brakes once your vehicle speed reaches 40 mph. Your brakes should be applied hard enough to reduce your speed to 35 mph.
Once your vehicle speed reaches 35 mph, release the brakes. Repeat this procedure as often as necessary until you have reached the end of the downgrade.
This braking technique is called snubbing.