Primary succession is taking place. lichens are most often found on exposed rock and are the organisms responsible for initial
soil and humus buildup. all but one is a feature of lichens that manage such a feat.

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%

the answer is c. it will give up it's valence electron to the other atom.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.

bal is blood alcohol level. bac will normally be higher in a person with more body fat. so the answer to your question would be, as body fat decreases, the increasing rate of bal decreases.