Final answer:
The question about front brake limiting valves pertains to their function in reducing air pressure to the front brakes, which is not specifically detailed in the provided materials. The materials focus on hydraulic brakes and Pascal's principle.
Step-by-step explanation:
The function of front brake limiting valves is to modulate the air pressure to the front brakes to prevent over-braking and potential loss of vehicle control. While the question seems to be asking for the specific ratio by which these valves reduce air pressure, this detail is not explicitly addressed in the provided materials. The information provided is related to hydraulic brakes and Pascal's principle, describing how force is transmitted through a fluid in a hydraulic system to achieve braking. Typically, the force distribution in brake systems is carefully calibrated for safety and effectiveness, but an exact ratio would need to be specified by the vehicle's manufacturer or found in a technical manual for braking systems.