Problem $1(10$ pt$.)$:

For aircraft wing in problem is schematically represented as a cantilevered beam. Calculate the tip $($point $A)$ deflection and rotation for this beam using Castigliano's theorem $($Energy Method$).$ The elastic modulus of the $7076$ Al alloy is $E=70$GPa, moment of inertia of the beam cross$-$section area along bending axis is $I_{xa}=4830*{10}^{-6}m{m}^4.x$ The weight of the engine is $20$ kN $.$