I'm studying about the senses and I'm responsible for the sense "Smell". But I don't know what to do in these tasks. Can you pls help me?

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

If water were a non polar molecule, how would its properties be different ? a.) water would be a much lighter molecule b.) water would be able to climb up inside plants c.)water would not be able to form hydrogen bonds d.) water would stick together much more strongly