Question

calories given off when 81 {\rm g} of water cools from 46^\circ C to 23^\circ C

Answer 1

You are going to far too much trouble with your symbols. That 81 g is 81 g and there is nothing relative about it. I can't write a degree sign BUT it is easier to write the word degree than ^\circ C. Also, most people can read and know what degree means but ^\circ C means we must decipher the symbols.
q = mass water x specific heat water x (Tfinal-Tinitial)