Question

what should you do to maintain a constant speed while driving up a steep incline?

increase pressure on the accelerator pedal
gently apply the brake
maintain a firm hold on the steering wheel
decrease pressure on the accelerator pedal

Explanation:

When driving up a steep incline, gravity acts against the vehicle's motion. To counteract this and maintain a constant speed, more power is needed. The accelerator pedal controls the engine's power output. Increasing pressure on it provides more power to overcome the gravitational force. Gently applying the brake would slow the vehicle down. Maintaining a firm hold on the steering wheel is about control but doesn't directly address speed maintenance against the incline. Decreasing pressure on the accelerator would reduce power, likely causing the speed to drop.

Answer:

increase pressure on the accelerator pedal