Before driving a vehicle with a dual air brake system, how much air pressure should the air compressor build in both systems?

Answer: C — 100 psi

To ensure the safe operation of a vehicle equipped with a dual air brake system, it is crucial that the air pressure reaches an adequate level for effective braking performance. The correct threshold for the air compressor to build pressure in both systems is 100 psi. At this pressure, the air brake system can operate efficiently, allowing for proper functionality of the braking components. It ensures that there is enough air stored to activate the brakes effectively and maintain safety during operation. Maintaining the recommended air pressure is essential to prevent potential issues during driving, such as brake failure or reduced braking efficiency, which can lead to catastrophic consequences. Hence, knowing that the air pressure must reach at least 100 psi is vital for drivers of vehicles with dual air brake systems.