Pls give me one scientists who study or collect butterflies

the correct answer, according to e2020, is the second choice there is an occluded front in region a and a cold front in region b.

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.