To solve this problem it is necessary to apply the equations related to the conservation of momentum.
This definition can be expressed as

Where
= Mass of each object
= Initial Velocity of each object
= Final velocity
Rearranging the equation to find the final velocity we have,

Our values are given as

Replacing we have,


Therefore the final velocity is 6.5m/s
Answer:
According to studies, the milky way is approximately, "170,000–200,000 light-years (52–61 kpc) in diameter and, on average, approximately 1,000 ly (0.3 kpc) thick."
With that being said, it is safe to say that the dimensions are somewhere around 100,000 by 1,000
Answer: The amplitude is 0. (assuming that the amplitude ot both initial waves is the same)
Explanation:
When two monochromatic light waves of the same wavelength and same amplitude undergo destructive interference, means that the peak of one of the waves coincides with the trough of the other, so the waves "cancel" each other in that point in space.
Then if two light waves undergo destructive interference, the amplitude of the resultant wave in that particular point is 0.