To calculate the speed and velocity of the Ann`s we use the formula,

Here, d is distance and t is time and v if we take it with direction then it is called velocity and if we take it without the direction then it is called speed.
Given
and
.
Substituting these values in above equation we get

As Ann walked towards south direction therefore, Ann`s velocity is 3 mi/h south and her speed is 3 mi/h .
Ground water keept the ground at a stable level when it is gone the cavern it was in has no support and is at risk of callaps
Answer:
388.97 nm
Explanation:
The computation of the wavelength of this light in benzene is shown below:
As we know that
n (water) = 1.333
n (benzene) = 1.501

And, the wavelength of water is 438 nm
![\lambda (benzene) = \lambda (water) [\frac{n(water)}{n(benzene}]](https://tex.z-dn.net/?f=%5Clambda%20%28benzene%29%20%3D%20%5Clambda%20%28water%29%20%5B%5Cfrac%7Bn%28water%29%7D%7Bn%28benzene%7D%5D)
Now placing these values to the above formula
So,

= 388.97 nm
We simply applied the above formula so that we can easily determine the wavelength of this light in benzene could come
Answer:
The angle of incidence is greater than the angle of refraction
Explanation:
Refraction occurs when a light wave passes through the boundary between two mediums.
When a ray of light is refracted, it changes speed and direction, according to Snell's Law:
where
:
is the index of refraction of the 1st medium
is the index of refraction of the 2nd medium
is the angle of incidence (the angle between the incident ray and the normal to the boundary)
is the angle of refraction (the angle between the refracted ray and the normal to the boundary)
In this problem, we have a ray of light passing from air into clear plastic. We have:
(index of refraction of air)
approx. (index of refraction in clear plastic)
Snell's Law can be rewritten as

And since
, we have

And so

Which means that
The angle of incidence is greater than the angle of refraction
Explanation:
i hope this helps, its not the same person but its the same equation.