Can anyone please help me with these 3 sets of questions? I would appreciate an explanation too to actually understand the concept for myself. 1)

A Y5 kg welght-watcher wishes to climb a mountain to work off the equivalent of a large piece of chocolate cake rated at 911 (food) \"alories. How high must the person climb? The acceleration due to gravity is 9.8 m/ 5% and 1 food Calorie is 10% calories. Answer in units of km. A 40 g block of ice is cooled to 71C. It is added to 553 g of water in an 60 g copper calorimeter at a temperature of 23C. Find the final temperature. The specific heat of copper is 387 J/kg -C and of ice is 2090 J/kg -C. The latent heat of fusion of water is 3.33 x 10 J/kg and its specific heat is 4186 J /kg -C.. Answer in units of C. One liter of water at 38C is used to make iced tea. How much ice at 0C must be added to lower the temperature of the tea to 13C? The specific heat of water is 1 cal/g - C and latent heat of ice is 79.7 cal/g. Answer in units of g