Which substance is currently used for the bleaching of paper?

$O_2F_2$ is an unstable yellow-orange solid and $H_2O_2$ is a colourless liquid. Both have an $O-O$ bond. The $O-O$ bond length in $H_2O_2$ and $O_2F_2$ respectively is:

Hydrogen peroxide is stored away from light because it can get decomposed when exposed to light as:

The products obtained from a reaction of hydrogen peroxide and acidified potassium permanganate are

Which is the correct order of stability for the given oxygen species?

How many millilitres of $20$ volume $H_2O_2$ solution is needed to react completely with $500 \ mL$ of acidified $1 \ N \ KMnO_4$ solution?