Construct an argument that shows that the set of rational numbers is closed under addition. That is, if x and y are rational numbers and w=x+y, prove that w must also be a rational number.

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.

Can some one explain this i got sent this. is this a threat i’m scared

If on=8x-8,lm=7x+4,nm=x-5,and ol=3y-6