Newton's Law of Cooling
Tf=Ts+(Ti-Ts)e^(-kt) where Tf is temp at time t, Ts is temp of surroundings, Ti is temp of object/fluid. So we need to find k first.
200=68+(210-68)e^(-10k)
132=142e^(-10k)
132/142=e^(-10k)
ln(132/142)=-10k
k=-ln(132/142)/10
k≈0.0073 so
T(t)=68+142e^(-0.0073t) so how long until it reaches 180°?
180=68+142e^(-0.0073t)
112=142e^(-0.0073t)
112/142=e^(-0.0073t)
ln(112/142)=-0.0073t
t= -ln(112/142)/(0.0073)
t≈32.51 minutes
The simplest form for this fraction is (A)
You divide both the numerator and denominator by 9, you will get 3/5.
so the answer is A.
319049
as 100,042 + 98,117 + 120,890 = 319,049
Answer:
1/4
Step-by-step explanation:
For the first circle 2 x 2in = 4 to find diameter
4 x 3.14 = 12.56
6in x 2 = 12
12 x 3.14 = 37.68
simplify
12.56/37.68
6.28/18.84
3.14/9.42
So the answer is 1/4 since 3.14 x 2 = 6.28
Also since the radius is 2 times longer
