Answers to first part (stability): Note that trace = f'(x) - e and det = e ( g'(x) - f'(x) ) (where 'x' is the steady state shown in the picture). So, taking into account whether f'>0, g'>0, g'(x) > f'(x), etc, we can say: (a) stable (b) stable (c) unstable but we know more: if also 0 < e << 1 then f'(x)-e > 0 (because f'(x)>0) so we have an unstable node or unstable spiral, that is to say, we have a "repelling" point (as required for Poincare'-Bendixon) (d) saddle