Hello humans~
help me with these questions

Which one of the following gases is not an important component of soil?

When svante arrhenius first proposed his acid-base theory, he was a doctoral candidate. his professors thought his ideas were unfounded. within a decade, the arrhenius theory of acid-base was widely accepted and praised within the scientific world. arrhenius defined acids as compounds having ionizable hydrogen and bases as compounds with ionizable a) barium. b) hydronium. c) hydroxide. d) oxygen.

6what is the importance of water on earth? a) it keeps the top layer of the geosphere cool b) it allows life to exist c) it provides ice at the poles d) it creates earth's blue color from space