A slope field for dtdy=g(y) shows horizontal tangents at y=2. Just above y=2 the arrows point downward, and just below y=2 the arrows point upward.
Which of the following best describes the nature of the equilibrium solution y=2?
a) It is neutrally stable because nearby solution curves remain at a constant distance from y=2.
b) It is unstable because solution curves on both sides move away from y=2.
c) It is stable because solution curves on both sides move toward y=2.
d) It is semi-stable because solution curves move toward y=2 from below and away from it from above.