Which of the following is true about a phase plot for an autonomous differential equation? [There may be multiple true statements, so mark all of them] Group of answer choices A phase plot has x as its horizontal axis and y as its vertical axis. If a phase plot crosses from a negative value to a positive value at an equilibrium, that equilibrium is unstable. Equilibria correspond to where the phase plot intercepts the horizontal axis. When the phase plot is above the horizontal axis, we decorate that portion of the horizontal axis with right arrows.