$10\mathrm{.}6$ In flowing from section $(1)$ to section $(2)$ along an open channel, the water depth decreases by a factor of $2$ and the Froude number changes from a subcritical value of $0\mathrm{.}5$ to a supercritical value of $3\mathrm{.}0.$ Determine the channel width at $(2)$ if it is $12$ ft wide at $(1)\mathrm{.}10\mathrm{.}6$ In flowing from section $(1)$ to section $(2)$ along an open channel, the water depth decreases by a factor of $2$ and the Froude number changes from a subcritical value of $0\mathrm{.}5$ to a supercritical value of $3\mathrm{.}0.$ Determine the channel width at $(2)$ if it is $12$ ft wide at $(1).$