The driver of a car made an emergency stop on a
straight horizontal road. The wheels locked and
the car skidded to a stop. The marks made by the
rubber tires on the dry asphalt are 16 meters long,
and the car's mass is 1200 kilograms.

Calculate the magnitude of the frictional force the road
applied to the car in stopping it. [Show all work,
including the equation and substitution with units.]