You need to look up the specific heat capacity of water. Think about the units of specific heat capacity and the units of the quantities in the question. How can these all be combined to give you an answer in the correct units?
Well, it's easy to look up the specific heat capacity for water... just type it into Google or something. Then you need to think about how to use this information - again, the units will be a big hint and will tell you what the specific heat capacity represents.