$\delta = \delta_T$
$\dfrac{PL}{AE} = \alpha \, L \, \Delta T$
$P = \alpha \, \Delta T \, AE$
$P = (11.7 \times 10^{-6})(80 - 25)(90 \times 12)(200\,000)$
$P = 138\,996 \, \text{N}$
$F = 2P$
$pDL = 2P$
$p(2000)(90) = 2(138\,996)$
$p = 1.5444 \, \text{ MPa}$ answer