Answer:
the first one is D
Explanation:
so if the others u put are right the the second would be c
If a hot air balloon has shown rising above the top of a hill, the top of the hill is considered as a reference point.
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Reference Point:</h2>
It is a point that is used to standardize a experiment. The reference point is a constant point.
In the given problem:
- The hot air balloon is rising above the top of the hill. Here, the hill is a standard point that has a fixed (constant) height.
- Some other reference points are the top of the Eifel Tower or a famous shop which a person use to denote a certain distance.
Therefore, "If a hot air balloon has shown rising above the top of a hill" the top of the hill is considered as a reference point.
Learn more about Reference Point:
brainly.com/question/1674904
Answer: 3 m/s
Explanation:
We can solve the problem by using the law of conservation of momentum: during the collision between the two balls, the total momentum of the system before the collision and after the collision must be conserved:

The total momentum before the collision is given only by the cue ball, since the solid ball is initially at rest, therefore

So, the final total momentum will also be

And the total momentum after the collision is given only by the solid ball, since the cue ball is now at rest, therefore:

from which we find the velocity of the solid ball
