What are the different possible oxidation states exhibited by scandium $(Sc)$?

Among the following,the incorrect statement about transition metals is:

Although Zirconium belongs to the $4d$ transition series and Hafnium to the $5d$ transition series,they show similar physical and chemical properties because . . . . . . .

Which element from the following is $NOT$ regarded as a transition element?

Why is $Cr^{2+}$ reducing and $Mn^{3+}$ oxidising when both have $d^{4}$ configuration?

The metal ion having maximum paramagnetic behaviour among the first transition series elements is,