4+ [(16 - 4) + (12 -9)] also explain the answer and you

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

Three students, javier, sam, and corrine, participated in a fundraiser where people donated a certain amount of money per lap that the student ran. each student also had some initial donations that were collected before the run. the equations that represent each student's total donation, y, based on the number of laps ran, x, is shown below. match each equation with the correct rate of change for that student.

Leonardo wrote an equation that has an infinite number of solutions. one of the terms in leonardo’s equation is missing, as shown below.