Change in the external Environment may resulted in the changing in the population of beetles.
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
1. Radiometric, Relative
2. Radiometric Dating
3. Relative Dating
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