Answer:
32
Step-by-step explanation:
M: 22
T:19
W:33
Th: 2m, if m=22, Th=44
22+19+33+44=118
150-118=32
So he played for 32 minutes on Friday
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:
A = 120 cm^2
Step-by-step explanation:
The formula for surface area of a rectangular prism is:
A = 2(area of the top) + 2(area of the front) + 2(area of one side)
Substituting the values:
A = 2(20) + 2(16) + 2(24)
First, distributing:
A = 40 + 32 + 48
Then adding, giving your final answer
A = 120 cm^2
Hope this helps you :)
