During an ice skating performance, an initially
motionless 80.0-kg clown throws a fake barbell away. The clown’s
ice skates allow her to recoil without friction. If the clown
recoils with a velocity of 0.500m/s and the barbell is thrown with
a velocity of 10.0m/s.

a)Determine the mass of the barbell;

b)The clown throws the barbell in 0.40-s, determine the
force exerted to the barbell by the clown.