The internal temperature of roast beef is 180°F when it is removed from the oven. It is set on a kitchen counter where the room temperature is 75°F. Use Newton's Law of Cooling with a rate of
k = -0.06 to determine after how many minutes the temperature of the roast beef will be 3/5 of the original
temperature. Round to the nearest 1000th
T=T, + (T, -T,)e"