Longitudinal Stress:
$F = pA = 125 [ \, 1.5(2) + \frac{1}{4} \pi(1.5)^2 \, ](12^2)$
$F = 85\,808.62 \, \text{lbs}$
$P = F$
$\sigma_l [ \, 2(2 \times 12) ( \frac{1}{8} ) + \pi (1.5 \times 12) ( \frac{1}{8} ) \, ] = 85\,808.62$
$\sigma_l = 6\,566.02 \, \text{psi}$
$\sigma_l = 6.57 \, \text{ksi}$ answer
Circumferential Stress:
$F = pA = 125[ \, (2 \times 12)L + 2(0.75 \times 12)L \, ]$
$F = 5250L \, \text{ lbs}$
$2T = F$
$2[ \, \sigma_t ( \frac{1}{8} )L \, ] = 5250L$
$\sigma_t = 21\,000 \, \text{psi}$
$\sigma_t = 21 \, \text{ksi}$ answer