A 4kg dog initially running at a velocity of 2m/s accelerates to a velocity of 7 m/s. What is the impulse on the dog? Responses 90 kgm/s 90 kgm/s -90 kgm/s -90 kgm/s 180 kgm/s 180 kgm/s -180 kgm/s -180 kgm/s -20 kgm/s -20 kgm/s 20 kgm/s