1. How does the back wheel of a bicycle turn if the torque of the chain/gear is applied at the center of the wheel?

Question

2. In a real bicycle, the normal force on the front wheel from the ground acts slightly away from the vertical line passing through its centre. The average normal force on the front wheel acts
A. ahead of this line.
B. behind this line.

3. A free wheel is rolling without slipping on a rough horizontal surface. The magnitude and direction of the frictional force on the wheel are
A. non-zero, backward.
B. non-zero, forward.
C. zero, undefined.

4. Why does the bicycle stops if pedaling is stopped?