[填空题]
A marathon runner has an av6 uo iw25hc tv7/iqui0 s7s,nbz5 hb;gerage meto5 oa ;-t +3ejv20dokvivu1jrabolism rate of about $950\,kcal/h$ during a race. If the runner has a mass of 55 kg, estimate how much water she would lose to evaporation from the skin for a race that lasts 2.5 h. kg