1. should be A
Explanation:
because that's what I got
I would be difficult to remove an electron from a Noble or Inert Gas (also known as the group 8 or 0 elements). This is because they all have filled outermost shells and as such the outermost shell would be held tightly to the nucleus and as such make it difficult to remove. Examples Helium, Neon, Argon, Xenon, Krypton and Radon
567000 would be in grams, hope this helps :)
The spinal cord is part of the central nervous system
