Lithium has 3 electrons. why do 2 electrons go in the first shell, and one in the second?
question 2 options:

a. the electrons go randomly into shells

b. the first shell only holds 2 electrons so the 3rd electron had to go in the second shell

c. all the electrons could go into the second shell.

d. the shells appear and disappear so the electrons go anywhere

Depending on the organism the number of in a cell may change

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone