About of Newton's law of cooling

And is that you use that to calculate the decrease of a hot body for a cooler ambiance, example, that suppose to be used in movies of murder, but returning of the hot coffee cup with 95°C and the environment that is the 20°C of temperature, the law is that the dT/dt=K(T - T0) where T is the actual temperature of the hot cup and the T0 is the temperature of the environment, so think that the temperature of the environment is to be constant, so use the same thought to a person that die in the cold night, see the outside is so big that is the same of a room with controlled temperature, if the person knows the temperature of that night could use the Newton law for a person that dies of cold, is exponential decrease. Rute Bezerra de Menezes Gondim