I NEED HELP BEFORE 10:00 A. M! (please no lengthy explanations, I will be attaching an image with the question shortly)!

If you can solve all of these i will give ! - 4% of 190 - 4% of 162.5 - 4% of 140 - a 4% increase from 155.1 - a 4% increase from 159.8

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab

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