What is all necessary for natural selection to occur?

4.06 hc)a five-year review of threats to the southern resident orca population of the united states concluded that the top threats were prey availability, contaminants, and effects from recreational and whale watching vessels. further down the list are oil spills, disease, and effects from commercial vessels not targeting whales. how might this list be different if it were for transient whale populations, which have a larger average population size and live farther offshore in open waters? a)the transient population is more likely to be affected by contaminants. b)the transient population is less likely to be affected by whale watching vessels. c)the transient population is more likely to be affected by disease. d)the transient population is less likely to be affected by prey availability.

Which is an example of a vestigial structure? a. tail of a monkey b. fin of a fish c. flower of a plant d. tailbone of a human

Easy 6th grade work! 100 points! i need fast! compare the parts of a cell and the cell as a whole to another common nonliving system (i. e., a car, a city, describe the parts of a cell and their primary function.