A sealed flask with a capacity of $2 \mathrm{dm}^3$ contains 11 g of propane gas. The flask is so weak that it will burst if the pressure becomes 2 MPa . The minimum temperature at which the flask will burst is $\_\_\_\_$ ${ }^{\circ} \mathrm{C}$. [Nearest integer] (Given: $\mathrm{R}=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$. Atomic masses of C and H are 12 u and 1 u respectively.) (Assume that propane behaves as an ideal gas.)