Where the values kA and kI can be freely chosen. (a) Find the characteristic equation of this system. (b) For what values of kA and kI will the system be stable? (c) If kA = 10 and kI = 100 how many roots of the characteristic equation will be positive? How do you know? (d) If kI = 100 for what values of kA will the system be marginally stable? Find the root(s) of the characteristic equation associated with this stability.