on a body is produced by the gravitational force of attraction​

Hey

muscuels should be your answer, with out gravity your musclues would become very weak. that's why astronauts on the ISS have to exercise daily.

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

the bal will not change its velocity.