Two Elastic/Inelastic Questions - Really Easy

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In the discussion, a scenario involving a collision between a 6kg green ball and a 3kg yellow ball is analyzed, with the green ball's speed decreasing after the collision while the yellow ball gains speed. The participants debate whether the collision is totally inelastic, inelastic, or indeterminate based on the given information, with a consensus leaning towards option three, indicating an inelastic collision. The second scenario involves an open cart collecting rainwater while rolling, prompting questions about the mass change due to conservation principles, with one participant suggesting the mass decreases due to conservation of momentum. However, there is uncertainty regarding the correctness of the answers provided for both problems. Overall, the discussion highlights confusion over the principles of momentum and energy conservation in these scenarios.
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A 6kg green ball with a speed of 2 m/s travels to the right and strikes a yellow ball of 3kg initially at rest. After the balls collide, the green ball continues to the right with a speed of 1 mls and the yellow ball moves to the right with a speed of 2 m/s Which of the statements is true?

1, The type of collision cannot be determined from the information given.
2. THe collision was totally inelastic.
3. The collision was inelastic.

I think it is 3 but I am not certain.

An open cart on a level surface is rolling without fricitonal loss through a vertical downpour of rain. As the cart rolls, rainwater accumulates in the cart. The mass will:

1. Decrease because of conservation of momentum.
2. Decrease because of conservation of mechanical energy.
3. Remain the same.

I think it is 1.

So you know - I am not cheating. I already did the quiz and got these questions wrong.
 
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None of the answers (1,2,3) look right in both of the problems.
 
I meant in the second question.
 

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