I was editing this question the other day, and the user was working with both heat capacity ($C_p$) and temperature ($\mathrm{°C}$), but they had been using $C$ throughout the whole problem. Once I had gotten through editing the answer, they asked the question:
In the first equation, what does $C$ designate?
What do you do in situations like these? I answered this question through editing it, but that isn't quite a formal answer.