A fan that can provide air speeds up to 55 m/s is to be used in a low-speed wind tunnel with atmospheric air at 23ºc. if one wishes to use the wind tunnel to study flatplate boundary layer behavior up to reynolds numbers of rex= 108, what is the minimum plate length that should be used? at what distance from the leading edge would transition occur if the critical reynolds number were rex,c= 5 à 105?