Latent Heat: 180kcal Lost in 30 Min, How Much Water?

[geah]

The question reads:

During exercise a person may give off 180kcal of heat in 30 min by evapouration of water from the skin. How much water is lost?

If someone could clearly explain the question that would be great thanks

 

[Shooting Star]

When water evaporates, a certain amount of heat is needed to transform the water to vapour at the same temperature. The amount of heat necessary per unit mass is called the latent heat of evaporation and is equal to 540 cal/gm.

When a person sweats, the water evaporates, and the latent heat is supplied by the body of the person, thus cooling the body.