a$)$ Explain how a finite wing creates a downwash and discuss the implications of the downwash on the drag of the wing. b$)$ A light aircraft is flying at a speed of $216$ km$/$h at an altitude where the air density is $1\mathrm{.}2$ kg$/$m$3.$ The wing has an elliptical lift distribution, a wing loading of $2$ kN$/$m$2,$ and is untwisted with the same symmetric section from the root to the tip. If the wing has an aspect ratio of $6,$ a wingspan of $12$ m and a lift curve slope of $6($rad$),$ find the lift force per span, lift coefficient and induced$-$drag coefficients of the wing. Furthermore, find the effective, induced and absolute angles of attack. What is the power that would be required to overcome the induced drag?