Ihave gotten this wrong 4 times already

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?

Which expression is equivalent to sq-80

What is the volume of a cone with a height of 6 cm in the radius of 2 cm