30. Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance.
a. perception.
b. reaction.
c. brake lag.
d. effective braking.
31. The most common type of foundation brake found on heavy vehicles is the:
a. Disc.
b. Wedge drum.
c. S-cam drum.
d. None of the above.
32. Parking or emergency brakes of trucks and buses can be legally held on by _____ pressure.
a. spring.
b. fluid.
c. air.
d. atmospheric.
33. If the air compressor develops a leak, what keeps the air in the tanks?
a. The tractor protection valve.
b. The emergency relay valve.
c. The one-way check valve.
d. Nothing.
End of CDL Air Brake Test.
Page 5 answers: (30)c (31)c (32)a (33)c
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