Answer
Please see the work below.
Work Step by Step
We know that
$Heat \space of\space condensation=\frac{2.26\times 10^3J}{1g}\times 168g=3.7968\times 10^5J$
Now we can find the temperature change as
$Temperature \space change =\frac{3.7968\times 10^5J}{6.44\times 10^4g}\times \frac{1gC^{\circ}}{1.015J}=5.81C^{\circ}$
