Caliometry help please?

If 25.0 mL of a 0.100 M aqueous sodium hydroxide is mixed with 25.0 mL of a 0.100 M aqueous hydrochloric acid in a calorimeter at an initial temperature of 23.0 degrees Celsius, what is the enthalpy change of this reaction if the final temperature reached in the calorimeter is 25.5 degrees Celsius?