Answer:
The rate at which energy is transferred is called power and the amount of energy that is usefully transferred is called efficiency.
Answer:
friction
Explanation:
Her brakes will squeak and possibly slide or skid on concrete due to her brakes.
BUT it really depends on the condition of the wheels. Now it matters on the surface as well. Has the road been eroded? what has happened with her brakes? and what texture are the wheels? can seismic waves travel through them?
The force ffrom the ground that holds the rock up and prevents her from falling through the gound, unless the ground breaks.
