$(a)$ ${CrO}_{3}$ $(b)$ ${Fe}_{2} {O}_{3}$ $(c)$ ${MnO}_{2}$ $(d)$ ${V}_{2} {O}_{5}$ $(e)$ ${Cu}_{2} {O}$
$(b)$ $\stackrel{+3} {Fe}_{2} {O}_{3}$
$(c)$ $\stackrel{+4} {MnO}_{2}$
$(d)$ $\stackrel{+5} {V}_{2} {O}_{5}$
$(e)$ $\stackrel{+1} {Cu}_{2} {O}$
So order of oxidation state $a>d>c>b>e$
(પરમાણ્વીય ક્રમાંક : $Ti = 22,\,Cr = 24,$ $ Mn = 25,\,Ni = 28$)