Which element from the following exhibits the highest number of various different possible oxidation states?

Determine whether the following statements are True $(T)$ or False $(F)$:
$(a)$ Transition elements exhibit variable oxidation states.
$(b)$ The $E^o$ values for $Mn, Zn,$ and $Ni$ are more positive than expected from the general trend.
$(c)$ Any metal exhibits its maximum high oxidation state in oxide and chloride compounds.

Which of the following pairs has a similar magnetic moment?

How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?

Match Column $A$ with Column $B$:

Column $A$	Column $B$
$(1)$ $V^{4+}$	$(a)$ Colorless
$(2)$ $Ti^{3+}$	$(b)$ Pink
$(3)$ $Ti^{4+}$	$(c)$ Purple
$(4)$ $Mn^{2+}$	$(d)$ Blue
	$(e)$ Violet

The transition metals are mostly