A. Physics
The study of how objects interact with each other
Answer:
Explanation:
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Space debris that enters earths atmosphere
Answer:

Explanation:
The vertical component of the initial velocities are

If we ignore air resistance, and let g = -9.81 m/s2. The the time it takes for the projectiles to travel, vertically speaking, can be calculated in the following motion equation




So the ratio of the times of the flights is

isotopes are the same element, but have different numbers of neutrons (but still have the same number of electrons and protons), hence have a different mass number.