Answer
Please see the work below.
Work Step by Step
We know that the heat absorbed from the water is
$Q_c=mL_f$
We plug in the known values to obtain:
$Q_c=(0.670)(334000)$
$Q_c=223780J$
For a refrigerator
$COP=\frac{Q_c}{W}$
This can be rearranged as:
$W=\frac{Q_c}{COP}$
We plug in the known values to obtain:
$W=\frac{223780}{4.2}$
$W=53000J$
