Beer & Johnston — Stress and Strain—Axial Loading: Problem 2.20

2.20 The rod $ABC$ is made of an aluminum for which $E = 70\text{ GPa}$. Knowing that $P = 6\text{ kN}$ and $Q = 42\text{ kN}$, determine the deflection of (a) point $A$, (b) point $B$.