P
1 = 6000 lb tension
P
2 = 1000 lb compression
P
3 = 4000 lb tension
$\delta = \dfrac{PL}{AE}$
$\delta = \delta_1 - \delta_2 + \delta_3$
$\delta = \dfrac{6000(3 \times 12)}{0.5(10 \times 10^6)} - \dfrac{1000(5 \times 12)}{0.5(10 \times 10^6)} + \dfrac{4000(4 \times 12)}{0.5(10 \times 10^6)}$
$\delta = 0.0696 \, \text{ in. (lengthening)}$ answer