Answer:
An acute angle is an angle less than 90°
Exponential model is y=Ae^(kt)
Assume initial start is 2005, time = 0, so y = 18000e^(kt)
45000 = 18000*e^(k5)
solve for k, approx 0.1832
y = 18000*e^(1.832) = 112,435, approximately
Answer:
It isn't necessary but having a positive coefficient for 
makes things like completing the square and factoring easier.
if 35 is LESS than 39
so +35 - 39 is -4 F°
the answer to the freezing point of (hehe) butter is -4 F°
