Answer :
Final answer:
The low-pressure warning device should activate at 50 psi to alert drivers before the air tank pressure in commercial vehicles drops below a safe level.
Explanation:
The low-pressure warning device should activate at a specific pressure to ensure the safety of pneumatic systems, such as those used in vehicle braking systems. The correct answer to this question is b) 50 psi. Commercial vehicles are required to have a low-pressure warning device that activates and alerts the driver before the air tank pressure drops below a safe level for vehicle operation. Activation levels can vary by jurisdiction and type of vehicle but typically range around this value.
