Is the acceleration of a car greater when teh accelerator is pushed to the floor or when brake pedal is pushed hard?

What is the acceleration of a pebble thrown vertially upwards when the pebble is falling down?

Two persons manage to push a motor car of mass 1,200 kg at uniform velocity on the road. The same motor can be pushed by three persons to produce an acceleration of 0.2 ms^(-2) . With what force does each person push the motor car ?( Assume that all persons push motor car with same muscular effort.)

What is the acceleration of a pebble thrown vertially upwards when the pebble is at the maximum height.

What is the magntiude of transverse acceleration produced in the motion of the electric charge, when it passes through the electric field?

Soni says that the acceleration in an object could be zero even when several forces are acting on it. Do you agree with her?why?