A twin$-$engine aircraft with a wing loading $($W$/$s$)$ of $500$ kgf$/$m$2,$ a wing area of $100$ m$2,$ and a single$-$engine reaction force of $2500$ kgf at ISA sea level conditions is in horizontal flight at an altitude of h$=5000$ m with the throttle fully open. The two known points on the polar curve of the aircraft are $($CD$,$ CL$)=(0\mathrm{.}02$ ; $0)$ and $($CD$,$ CL$)=(0\mathrm{.}04$ ; $0\mathrm{.}8).$ The density of air for h $=5000$ m is $0\mathrm{.}736$ kg$/$m$3.$ Calculate the horizontal flight speed of the aircraft at h$=5000$ m based on the given information.