On steep mountain grades, __________ are built to stop runaway vehicles safely without injuring drivers or passengers.

I believe the answer is: Escape ramp
Escape ramp is designed for vehicles that having problems with their brake to safely stop. It is usually made using sand filled lane connected to a steep downhill in order to increase the friction that prevented the wheel form moving forward.

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holesstanham holesstanham · Answer 2 · 2019-04-27T18:20:52+02:00

Answer:

Escape ramp

Explanation:

Escape ramps are usually located on steep areas, most often in mountains. Because of the long descending grades that are present in these areas, cars can achieve a high speed and brakes can overheat and fail because of extensive use. Therefore, in order to reduce accident and to protects drivers and passengers, escape ramps are placed as a safe way for cars to stop. A escape ramp is a long lane that is typically filled with sand or gravel. This allows vehicles with braking problems to safely stop.