Bart walked at 8km/h for 25 km, how long did his walk take him to complete?

3 hours 7 minutes 30 seconds

Explanation:

if you divide 25 by 8 you get 3.125 so that is three hours and 1/8th of an hour which is 7 minutes and 30 seconds

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.