Drying and Dehydration

The latent heat of sublimation of ice at $-10^\circ\text{C}$ is $h_{sub} = 2838\text{ kJ/kg}$. To sublime $m = 5.0\text{ kg}$ of pure ice during primary freeze drying, the total thermal energy required $Q = 5.0 \times 2838$ in kJ is: