A Boeing $737$ fully loaded has a take$-$off mass of $60,000kg.$ The planform area of its wings is $125m^2.$ When rolling down the runway, the angle of attack of the wings to the oncoming air is $15.$ Determine the minimum take off speed $($mph$)$ for BWI Airport $($sea level elevation with atmospheric conditions at $101$ kPa and $25C),$ and for Denver Airport $($same temperature, with a pressure of $87$ kPa $).$ Assume a NACA $23015$ airfoil $($figure $1\mathrm{.}64)($The Reynolds number for flow over the wings will be very high.$)$

Ans: $v_1=157mph,v_2=169mph$