Temperature Calculus nEED HELP ASAP PLS!

Question

 

The temperature of a cup of coffee varies according to Newton's Law of Cooling: , where T is the temperature of the coffee, A is the room temperature, and k is a positive constant. If the coffee cools from 100°C to 90°C in 1 minute at a room temperature of 25°C, find the temperature, to the nearest degree Celsius of the coffee after 4 minutes. 

Answer Choices

74
	67
	60
	42

Answer 1

by understanding the concepts, you can avoid solving for k.

25 + (100-25)((90-25)/(100-25))^4 = 25 + 75 * (13/15)^4 = 67.31, which rounds to 67.