Solve Physics Calc: Energy Expenditure for Adam's Water Intake

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When Adam drinks cold water, his body warms the water until thermal equilibrium is reached. If he drinks six glasses (2.5 kilograms) of water at 0 degrees Celsius in a day, approximately how much energy must his body expend to raise the temperature of this water to his body’s temperature of 37 degrees Celsius?
The answer is 390kJ. Can someone help me with the working please. Thx.
 
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warrior86 said:
When Adam drinks cold water, his body warms the water until thermal equilibrium is reached. If he drinks six glasses (2.5 kilograms) of water at 0 degrees Celsius in a day, approximately how much energy must his body expend to raise the temperature of this water to his body’s temperature of 37 degrees Celsius?
The answer is 390kJ. Can someone help me with the working please. Thx.

WHat is the heat capacity of water? i.e., how much energy is required to raise one kilogram of water by one degree Celsius?
 
The heat capacity was not given in the question but if we assume it to be pure water, the heat capcity of water can be taken as 4.184 joules/g-°C.
 
4.184 joules/(g°C) * 2.5 kg * 37 ° C = ... :)