Which of the following is/are correct for the characteristics indicated against each ?

In case of oxy-acids of halogens, acidic strength increases with increase in number of oxygen atom.
Thus the correct acidic strength is $\mathrm{HClO}<{\mathrm{HClO}}_2<{\mathrm{HClO}}_3<{\mathrm{HClO}}_4$
For the given ions the correct order of oxidising power is ${{\mathrm{ClO}}_4}^{-}<{\mathrm{BrO}}_4^{-}<{{\mathrm{IO}}_4}^{-}$