How did dobzhansky and mayr explain the origin of species?

it happens through adaptation by natural selection.
it happens through sympatric speciation.
it happens through allopatric speciation.

Why does it matter if osmosis is put into a “scab” or a “nosebleed? ” where would that leave him?

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.

What type of plant is good for a bioassay and where can i buy it? i only have a month.