This the general question. the diagram is kinda missing
Consider a Boeing 727 flying at 5000m under standard atmospheric conditions associated with that altitude. It
is flying with a velocity of 810 km/hr.
The reference wing area S: 149 m2
The span b: 34.5 m
The span efficiency factor e1: 0.82
The profile drag coefficient (Cd) at 3 degrees angle-of-attack: 0.0062
Also known is:
The air density at h=5000m: ρ∞=0.736 kg/m3
The temperature at h=5000m: T∞=255.7 K
The static pressure at h=5000m: p∞=5.41⋅104 N/m2
The specific heat coefficient at constant pressure: cp=1008 J/kg K
Assume that the lift gradient of the wing under the actual flight conditions is 0.1179 per degree.
D) Calculate the lift-drag ratio of the wing at an angle of attack of 3 degrees.