in exercising, a weight lifter loses $0\mathrm{.}162$ kg of water through evaporation, the heat required to evaporate the water coming from the weight lifter's body. the work done lifting weights is $1\mathrm{.}75$x$10^5$ J$.($a$)$ assuming that the latent heat of vaporization of perspiration is $2\mathrm{.}42$x$10^6$ J$/$kg$,$ find the change in the internal energy of the weight lifter. $($b$)$ determine the minimum number of nutritional calories of food that must be consumed to replace the loss of internal energy. $(1$ nutritional calorie$=4186$ J$)$