For the reaction
`5Br^(-)(aq)+BrO_(3)^(-)(aq)+6H^(+)(aq)rarr 3Br_(2)(aq)+3H_(2)O(l)`
the reate expression was found to be `-(d[BrO^(3-)])/(dt)=k[Br^(-)][H^(+)]^(2)[BrO_(3)^(-)]`
Which of the following statements is /are correct?
I. Doubling the intial concentration of all the reactants will increase the reaction rate by a factor of 8.
II. Unit of rate constant of the reaction in a buffer solution is `"min"^(-1)`
III. Doubling the concentration of all the reactants at the same time will increase the reaction rate by a factor of 16
IV. rate of conversion of `BrO_(3)^(-)` and rate of disappearance of `Br^(-)` are the same