How much heat energy in megajoules is needed to convert 7 kilograms of ice at -9c to water at 0c?

To convert 7 kilograms of ice at -9°C to water at 0°C, you need to calculate the energy required for each phase change. First, calculate the energy to raise the ice temperature from -9°C to 0°C using the specific heat capacity of ice. Then, calculate the energy required to melt the ice into water using the latent heat of fusion of ice. The total energy will be the sum of these two values.