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
Primary succession is when, for example, a volcano explodes and there is nothing left and even the soil is ruined. It would take at least a hundred years for the land to be like it was before the volcano erupted. Secondary succession is when, for example, a wild fire happens but the soil is not ruined. It would take at least 25-50 years for the land to be like it was before the fire.
Homointernal adalah hewan yang bersuhu tubuh panas dan tetap hewan-hewan ini adalah:
1)Ikan, terbagi
-ikan hiu
-ikan pari
2)Amfibi terbagi
-Kodok
3)Reptil
-buaya
-kura-kura
4)Burung terbagi
-ayam
-merak
-kasuari
