$\delta = \delta_T$

$\dfrac{PL}{AE} = \alpha \, L \, \Delta T$

$P = \alpha \, \Delta T \, AE$

$P = (11.7 \times 10^{-6})(80 - 25)(90 \times 12)(200\,000)$

$P = 138\,996 \, \text{N}$

$F = 2P$

$pDL = 2P$

$p(2000)(90) = 2(138\,996)$

$p = 1.5444 \, \text{ MPa}$ *answer*