An engine switched off and left to cool naturally will obey newtons law of cooling. A particular engine is switched off at 105°C when the ambient temperature is 0°C. Its temperature falls according to the equation T=105e-0.025t °C. Where t=time in minutes. c) use calculus to determine the rate of fall of temperature when t=80 minutes I have no clue where to start! no matter how hard i look there's nothing to help..