6.4.11 (Leftists, rightists, eentrists) Vasquez and Redner (2004, p. 8489) mention a highly simplied model of political opinion dynamics consisting of a population of leftists, rightists, and centrists. The leftists and rightists never talk to each other; they are too far apart politically to even begin a dialogue. But they do talk to the centriststhis is how opinion change occurs. Whenever an extremist of either type talks with a centrist, one of them convinces the other to change his or her mind, with the winner depending on the sign of a parameter r. If r > 0 , the extrem- ist always wins and persuades the centrist to move to that end of the spectrum. If r 0 and r =r For part c: I Use the numerical phase portrait to find the long-term behavior of the solutions