Answer
Its temperature would rise by $8670 \space K$.
Work Step by Step
$$\Delta U = C \Delta T$$ $$\frac{\Delta U}{C}= \Delta T$$ $$\frac{50.0 \space kJ}{5.77 \space JK^{-1}} = \Delta T$$
$$\Delta T = \frac{50.0 \space kJ}{5.77 \space JK^{-1}} \times \frac{1000 \space J}{1 \space kJ} = 8670 \space K$$
