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
Answer:
(4, 7)
Step-by-step explanation:
The point of interest is ...
P = (2Z +1Y)/(2+1) = ((2·3+6)/3, (2·9+3)/3)
P = (4, 7)
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The point that divides the segment into the ratio a:b is the weighted average of the endpoints, with the weights being "b" and "a". The weight of the first end point corresponds to the length of the far end of the segment.
Answer:
211 text messages
Step-by-step explanation:
20+(m•0.10)=41.10
41.1-20=21.1÷0.1=211
3(8)-12=12
24-12=12
The fourth choice.
Yeah I think you already got it
Answer:
C
Step-by-step explanation:
