For the first one I’d say D
The answer for the 2nd one is C.
The nucleus will have the greatest mass. Among the 3 kinds of subatomic particles, electrons are the lightest (by several orders of magnitude), protons and neutrons are much closer is magnitude, though neutrons are slightly heavier. However, in the diagram, the nucleus contains both the neutrons and the protons, so its combined mass would be heavier than either the neutrons alone or the protons alone.
Answer:
Ophthalmoscopy, also called funduscopy.
Well, depending on how long the migration is, many of the animals (mainly birds) could get sick and die, lowering the population. They could be shot by hunters, lowering the population. The children of the population could get left behind and lose their way, lowering the population. I'm not entirely sure how the population could grow other than them finding and staying with another group of their own kind. hope I was helpful! :)