Answer
$3.5\times 10^2~C^{\circ}$
Work Step by Step
We can find the required change in temperature as follows:
$\Delta T=\frac{D_{0,st}-D_{0,gl}}{\alpha_{gl}D_{0,gl}-\alpha_{st}D_{0,st}}$
We plug in the known values to obtain:
$\Delta T=\frac{1.000-1.003}{(3.3\times 10^{-6})(1.003)-(1.2\times 10^{-5})(1.000)}$
$\Delta T=3.5\times 10^2~C^{\circ}$
