The volume of a cube is 27 in^3 how long is each side? show and explain your work

How do you use the elimination method for this question? explain, because i really want to understand!

Mozart lenses inc. recently introduced seelites, a thinner lens for eyelasses. of a sample of 800 eyeglass wearers, 246 said they would purchases their next pair of eyeglasses with the new lenses. lenses inc. estimates that the number of people who purchase eyeglasses in a year is 1,700,000. most eyeglasses wearer buy one new pair of eyeglasses a year. what is the annual sales potential for the new lenses.

What three-dimensional solid have 6 rectangular faces, 2 equal bases that are not rectangles and 18 edges