v = average speed of movement of the Southwest Indian Ridge = 20 mm/year
d = distance moved by the Southwest Indian Ridge = 100 mm
t = number of years required to move distance "d"
distance traveled is given as
d = v t
inserting the above values in the formula
100 mm = (20 mm/year) t
dividing both side by 20 mm/year
t = 100 mm/(20 mm/year)
t = 5 years
Area is 2-dimensional which means it has a length and a width area is measured in square units such as square inches, square feet or square meters. To find the area of a rectangle multiply the length by the width.

Actually Welcome to the Concept of the Methods of Separation.
Evaporation and Decantation are the process which can be easily used to remove the Soluble Impurities.
Light travelling in a vacuum is the fastest thing in the universe. The speed would be 2.99x10^8 m/s. The answer to this question is 'vacuum', where light can travel the fastest. I hope this helps you. You're welcome!