Final answer:
In the previously assigned homework, charge-to-mass ratio was not used to determine the size of a DNA molecule.
Step-by-step explanation:
The size of a DNA molecule can be determined using various methods. In the homework assigned previously in this class, charge-to-mass ratio was not used to determine the size of a DNA molecule. The other options mentioned, such as number of base pairs, molar mass, and molecular mass can be used to determine the size of a DNA molecule.