this can be solve using the formala of free fall
t = sqrt( 2y/ g)
where t is the time of fall
y is the height
g is the acceleration due to gravity
48.4 s = sqrt (2 (1.10e+02 m)/ g)
G = 0.0930 m/s2
The velocity at impact
V = sqrt(2gy)
= sqrt( 2 ( 0.0930 m/s2)( 1.10e+02 m)
V = 4.523 m/s
<span> </span>
A group of students toured a limestone cave in northwest Georgia.
Which of these best explains how the limestone caves in Georgia were formed?
A. Plant roots split the rock.
B. Acidic water dissolved the rock.
C. Animals burrowed into the rock.
D. Ice formed and broke up the rock.
Answer: for insulation of heat
Explanation:
Windows in cold countries have double glazing windows to provide a barrier against the outside temperature by creating a buffer zone between two glasses.
The air or any other gas-filled between the glasses act as an insulator and offer great resistance to outside temperature thereby maintaining the inside temperature intact.

λ - wavelength, c - the speed of light, f - frequency
![f=200 \ kHz= 200 000 \ Hz \\ \\ \lambda=\frac{300 000 \ [\frac{km}{s}]}{200 000 \ [Hz]}=\frac{3}{2}=1.5 \ [km]](https://tex.z-dn.net/?f=f%3D200%20%5C%20kHz%3D%20200%20000%20%5C%20Hz%20%5C%5C%20%5C%5C%0A%5Clambda%3D%5Cfrac%7B300%20000%20%5C%20%5B%5Cfrac%7Bkm%7D%7Bs%7D%5D%7D%7B200%20000%20%5C%20%5BHz%5D%7D%3D%5Cfrac%7B3%7D%7B2%7D%3D1.5%20%5C%20%5Bkm%5D)
The wavelength of these waves is 1.5 km.