Answer
$144.5\,kJ/mol$
Work Step by Step
The equation $ZnO+S\rightarrow ZnS+\frac{1}{2}O_{2}$ is obtained by multiplying the first equation by $\frac{1}{2}$ and reversing it.
Therefore, $\Delta H^{\circ}_{rxn}=-(\frac{1}{2}\times-289.0\,kJ/mol)$
$=144.5\,kJ/mol$
