A coin is tossed twice. Let Z denote the number of heads on the first toss and W the total number of heads on the 2 tosses. If the coin is unbalanced and a head has a 40% chance of occurring, find (a) the joint probability distribution of W and Z; (b) the marginal distribution of W; (c) the marginal distribution of Z; (d) the probability that at least 1 head occurs.

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .

What is it called when part of a cell membrane closes around a molecule to allow the molecule to enter the cell? a. passive transport b.diffusion c. endocytosis d. exocytosisc. endocytosis

What would most likely happen to a unicellular organism if it was exposed to a hypotonic solution for an extended period of time?