There are three ways of abrasion occurs in nature; the wind, waves, and gravity. Abrasion is the mechanical process of wearing away of a rock surface and the movement of the particles while transporting through the wind, waves, and gravity.
Wavelength= velocity/frequency
wavelength= (3.0 x 10^8m/s) / 7.5 x 10^12 Hz)
you can do the math
I am assuming u that 108 is 10^8 and the 1012 is 10^12
If you have a book, read it!! I promise you, it tells you this answer!
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