The gas reaction $2$O$3->3$O$2$ takes place in a closed container. Initially $5\mathrm{.}8$ mol of O$2$ and $6\mathrm{.}2$

mol of O$3$ are present in the reactor. At some later time, the reactor is found to contain $7\mathrm{.}1$ mol of

O$3.$ At this time, what is the reaction extent and how much O$2$ is present in the reactor?