In: Electrical Engineering
The only that is 100% sure shot is that comparing the characteristics equation with the given equation and more precisely by observing the middle term in the denominator of the characteristics equation i.e. 2wn.
T.F= (k×wn)/(s2 +2×wn× +(wn)2 ) ; characteristic equation:- s2+ 2×wn××s +wn2
Where wn = undamped natural frequency, = damping factor.
Now as we know the conditions for different types of system i.e.
Now examples:-
There is no mention about non linear systems as I don't have any idea about that condition but apart from last condition given in the question for rest the above given descriptions is best suited. just remember the condition of for different system.