Answer:
When light enters from air to water i.e. it is moving from rarer to denser medium, it changes its original path as there is a change of speed of light and deflects itself towards the normal. This is known as the refraction of light and this is why a pencil in a cup of water looks as if it is broken and larger.
Explanation:
Option D) A drop of mercury is both a pure substance and and element.
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The speed of sound in fresh water is 1482m/s.
It says ocean floor, so we should a little bit more accurate, and use the fact that the speed of sound in salt water (that has no bubbles) is 1560m/s.
speed = distance / time
Therefore Distance = speed x time = 1560 x 3.3 = 5158m
The sonar wave is sent out by the boat, reflected off the seafloor, and then is received back at the boat on the surface. So the distance 5148m is the distance from the boat to the sea bottom and then back up to the boat again.
So the depth of the water is half this distance Depth of water = 5148/2=2574m
Length of the slope is given as

also the inclination is given as

now the horizontal displacement is let say "x"
now from geometry we can say


now substitute all values in it


<em>so it will displace horizontally by 12.99 m</em>