Question

You have a bottle of water. The water has a mass of 29 grams. You heat the water with 102 calories of heat and the final temperature of the water is 43°C. What was the initial temperature (in Celsius) of the water before you added the heat? The specific heat of water is 1 calorie / (°Cg).

Answer 1

q = mass H2O x specific heat H2O x (Tfinal-Tinitial)
You know q, mass H2O, specific heat and Tfinal. Solve for Tinitial.