A 3 kg cart (cart A) is released from the top of a ramp, as shown below. The cart travels down the curved part of the ramp (section 1) and travels on a frictionless horizontal surface (section 2). Cart A then collides with a second cart (cart B), which has a mass of 2 kg. Cart A Section 1 Cart B Section 2 Section 3 (a) Is the impulse of cart A positive, negative, or zero as it travel down the ramp in section 1? Briefly justify your answer.