Answer:
The angle of incidence at which total internal reflection takes place will be equal to 
Explanation:
We have given that light is traveling from a medium of refractive index x 2.7 to a medium of refractive index 1.6
So refractive index of first medium
and 
We have to find the angle of incidence for total internal reflection
For total internal reflection




So the angle of incidence at which total internal reflection takes place will be equal to 
If we take v=u+at and our given values are:
v=final velocity 20m/s
u=initial velocity 15m/s
a=acceleration
t=time 5sec
we plug those into our equation:
20m/s=15m/s+a(5s)
now we just rearrange to solve for acceleration.
(5m/s)/(5s)=a
a=1m/s^2
hope this helps!
PLEASE MARK BRAINLEIST
Answer:


Explanation:
<u>Rate of Change</u>
The volume of a cone of radius r and height h is given by

The height is said to be 1/2 of the radius, thus


a) Knowing r=18 feet, the volume is


b) The rate of change of the volume is computed by taking the derivative of both sides respect to the time


Where r' is the given rate of change of the radius: 2 feet/day.
Now we compute


Answer:The answer is B , 0.20 m/s south
Explanation:
Yeah, like a stop sign. We know it is most likely a stop sign since it has 8 sides or is an octagon.
I hope I helped!