Answer:
C
Step-by-step explanation:
Got it right on ed 2021
The answer is 78.5 because the formula to find area is πr2 so the radius is 5ft π is 3.14 so 3.14 times 5 and the 2 on top of r means the u have to do 5 times 5 which is 25 now it's real simple do 3.14 times 25 which is 78.5 I HOPE THIS HELPS=)
Well, there is nothing following, but if there is anything about K equal to or greater 4, or K being>2 than thats it.
Newton's law of cooling says the rate of change of temperature is proportional to the difference between the object's temperature and the temperature of the environment.
Here, the object starts out at 200 °F, which is 133 °F greater than the environment temperature. 10 minutes later, the object is 195 °F, so is 128 °F greater than the environment. In other words, the temperature difference has decayed by a factor of 128/133 in 10 minutes.
The solution to the differential equation described by Newton's Law of Cooling can be written as the equation
T(t) = 67 + 133*(128/133)^(t/10)
where T is the object's temperature in °F and t is the time in minutes from when the object was placed in the 67 °F environment.
The equation
T(t) = 180
can be solved analytically, but it can be a bit easier to solve it graphically. A graphing calculator shows it takes
42.528 minutes for the temperature of the coffee to reach 180 °F.