Which expression is equivalent to 5y+2y+6x+2y-x

Ibeg you to me 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?

Given right triangle a w/a hypotenuse length of x+4 and a leg of x, and right triangle b, w/ a hypotense length of 3y and a leg length of y+4 for what values of x and y are the triangles congruent by hl?

From a group of 10 men and 8 women, 5 people are to be selected for a committee so that at least 4 men are on the committee. howmany ways can it be done?