Answer:
gel electrophoresis
Step-by-step explanation:
Gel electrophoresis is a technique of cell biology capable of separating molecules making them migrate from one pole of the gel, to the opposite pole through a potential difference. This technique is perfect for determining the size of the molecules, because the smaller molecules are able to migrate from one pole to the other with greater speed than the larger molecules.
With gel electrophoresis, Loretta will be able to separate DNA molecules by size, helping her to determine the length of each molecule.