Answer:
Iron -> Fe - Group 8
Silver -> Ag - Group 11
Mercury -> Hg - Group 12
Oxygen -> O - Group 16
Gold -> Au - Group 11
Potassium -> K - Group 1
Xenon -> Xe - Group 18
Magnesium -> Mg - Group 2
Hydrogen -> H - Group 1
I believe its D. It becomes more difficult for the cell to get enough oxygen and nutrients.
Critical period because they had fully developed their vision
Answer:
the answer is c
Explanation:
theories can be modified with new empirical data
