(a) Variability ,No Variability

(b) Variability ,No Variability

(c) Variability ,No Variability

(d) Variability ,No Variability

(e) Variability ,No Variability

(f) Variability ,No Variability

(g) Variability ,No Variability

a Variability No Variability b Variability No Variability c Variability No Variability d Variability No Variability e Variability No Variability f Variability N class=