PLEASE PLEASE PLEASE HELP

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

If f(x) = 3x2 - 2x+4 and g(x) = 5x + 6x - 8, find (f-g)(x).

Segment wx is shown explain how you would construct a perpendicular bisector of wx using a compass and a straightedge