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:
Step-by-step explanation:
the first picture shows that two sides are the same and one angle so you know it's a SAS, the one tick mark and that the two trialge share one common side is how you know 2 sides are the same, and the 90 ° corner symbol shows you know an angle in each , that is also the same.
the second picture shows 3 sides the same so SSS, the triangles share one side, and have the tick marks, showing that each of the respective sides are the same.
:)
Average speed = total miles driven / total driving time
average speed = (150 + 100) / (3 + 1 1/2) =
250 / (4 1/2) =
250 / (9/2) =
250 * 2/9 =
500 / 9 = 55.55 mph
Answer:
Step-by-step explanation:
Perimeter of a rectangle = 2(L +W)
Given L = W + 2 and the perimeter is greater than 112 meters?
P rect < 2(L +W) L = W + 2
P rect < 2(W + 2 +W)
< 2(2W+2)
112 < 4W + 4 solve for W
(112 - 4)/4 < (4W +4 - 4)/4
108/4 < (4W + 0)/4
27 < W
the width has to be greater than 27 meters
Answer:
the
Step-by-step explanation:
it's fairly easy actually. You just have to use sin