Answer: Fractional distillation is used to separate liquids with differing boiling points
Explanation:
Sublimation is used to separate volatile substance from a non volatile substance where volatile substance gets converted from solid to gas.
Fractional distillation is separation of a liquid mixture into fractions which differ in boiling points by means of distillation by use of a fractionating column.
Chromatography is a separation method where different rates of adsortion of different components is used to separate substances.
If one is dilute, there is more water than substance dissolved in it. If it is concentrated, it has dissolved the maximum amount of the solvent dissolved in it.