The aluminum rod is fixed at its base and free and at its top. If the length of the rod is $L=2 \mathrm{~m}$, determine the greatest allowable load $P$ that can be applied so that the rod does not buckle or yield. Also, determine the largest sidesway deflection of the rod due to the loading. $E_{\mathrm{a}}=72 \mathrm{GPa}, \sigma_Y=410 \mathrm{MPa}$.