66. If you do not have automatic tank drains, how often should you drain the oil and water from the bottom of compressed air storage tanks?
At the end of each day of driving.
67. The proper use of the brakes when going down a long steep grade after selecting a proper gear is to brake until your speed is about ____ mph below the posted speed for your safety and release your brake.
5 mph
68. In ideal conditions, a truck or bus with an air brake going at 55 mph would require stopping distance of how many feet?
More than 300 ft.
69. When is it OK to leave your truck unattended without applying the parking brakes and choking the wheels?
Never
70. The stop light switch:
Turns on your brake lights to warn drivers behind you.