Someone pls help, I'm lost and confused. I have no idea what to do to.

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?

Askate shop rents roller skates as shown on the table below. which graph and function models this situation?

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g