Help please someone please

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

What is 1.5% of 120 or what number is 1.5% of 120

Which of the following constants can be added to x2 - 3x to form a perfect square trinomial?