At a certain temperature the rate of this reaction is first order in $S{O}_3$ with a rate constant of $0\mathrm{.}28s^{-1}$ :

$2S{O}_3(g)2S{O}_2(g)+O_2(g)$

Suppose a vessel contains $S{O}_3$ at a concentration of $1\mathrm{.}22M.$ Calculate how long it takes for the concentration of $S{O}_3$ to decrease to $7\mathrm{.}0\%$ of its initial value.

You may assume no other reaction is important.

Round your answer to $2$ significant digits.