Suppose we have a change equation for state variables R and S. What do the Snullclines represent? Select all that apply. The following checkbox options contain math elements, so you may need to read them in your screen reader's "reading" or "browse" mode instead of "forms" or "focus" mode. Choice 1 of 5:All the points where S is not changing. Choice 2 of 5:All the points where S is not changing. Choice 3 of 5:All the points where R is not changing. Choice 4 of 5:The equilibrium points of the 2D system. Choice 5 of 5:All the points where R is not changing