Consider the equations describing the interactions of robins r and worms w, dw/dt w - wr, and dr/dt = -r + rw. What are the (non-zero) nullclines for this system? W = r = Your nullclines divide the phase plane into four regions. Give a sample point in each region, and indicate for that point whether each of the populations is increasing or decreasing (by entering the word increasing or decreasing appropriate blank): (w, r) = (, ) is in one region, where the population of worms, w is and the population of robins, r is. (w, r) = (, ) is in a second region, where the population of worms, w is and the population of robins, r is. (w, r) = (, ) is in a third region, where the population of worms, w is and the population of robins, r is. (w, r) = (, ) is in the fourth region, where the population of worms, w is and the population of robins, r is. Notice what your conclusions about these four regions say about how the populations change with time.