1. x=0 is always a fixed point 
X = x/(x+c)
x^2 + cx = x
x^2 + (c-1)x = 0
X = 0, -(c-1)
-2<c<-1 for other stable fixed points
2.  
I. -16/3+5=-⅓, -7+13/2= -½, stable
Ii. 92/3-25=17/3, 35-57/2= 13/2, stable
Iii. -177/2+75/2= -27/4, -105/2+89/2= -8, stable