Select the incorrect statements :

 I) When a wire is stretched to three times its length, its resistance becomes9 times.

 II) Resistance of a given wire is directly proportional to length of wire

 III) V-I graph for a conductor at two different temperatures${\text{T}}_1{\text{\hspace{0.17em}and\hspace{0.17em}T}}_{\text{2}}$  are shown here ${\text{T}}_1>{\text{\hspace{0.17em}T}}_{\text{2}}$

IV) Resistance of a conductor increases with rise in temperature