1. The problem statement, all variables and given/known data The temperature T of a cup of coffee is a function T(t) where t is the time in minutes. The room temperature is 20 ^\circ Celsius. The rate at which the coffee cools down is proportional to the difference between the temperature of the coffee and the room temperature. Use this information to write a differential equation describing the derivative of the coffee temperature in terms of T and t. Use C as your proportionality constant. C should be a positive number. Write T instead of T(t). 2. Relevant equations 3. The attempt at a solution I don't know where to start.