According to Newton's empirical law of cooling-or warming-the rate at which the temperature of a body changes is proportional to the difference between the temperature of the body and the temperature of the surrounding medium, the so-called ambient temperature. A hot cup of coffee is initially at 180° F, sits in a room with a constant air temperature of 72° F, and cools according to Newton's law of cooling. Write an initial value problem describing the temperature of the coffee () at time t. Do not solve!