Answer
Please see the work below.
Work Step by Step
(a) As we know that
$Q=mL_f$
We plug in the known values to obtain:
$Q=2.5\times 10^{-13}\times 334$
$Q=8.35\times 10^{-11}KJ$
(b) As $P=\frac{Q}{t}$
We plug in the known values to obtain:
$P=\frac{8.35\times 10^{-11}}{1yr\times \frac{365days}{yr}\times \frac{24hrs}{day}\times \frac{3600s}{hr}}$
Now we can find Greenland's energy imbalance in $\frac{W}{m^2}$ as
$\frac{P}{A}=\frac{2.64\times 10^{-18}}{1.71\times 10^{12}}=1.54\times 10^{-18}\frac{W}{m^2}$
