A mining company would like to replace an old flow monitoring weir. The contracted $($one end$),$ horizontal weir has a crest height of $23\mathrm{.}5$ ft$,$ a crest length of $13$ ft$,$ and a discharge coefficient of $3\mathrm{.}28$ ft$0\mathrm{.}5/$s$.$ At design flow it operates with a head of $3\mathrm{.}6$ ft$.$ Determine the crest height of a standard U$.$S$.$B$.$R$.90\backslash$deg $-$V$-$notch $($replacement$)$ weir that would discharge the same design flow without raising the upstream flow depth.