Answer:
nanograms
Explanation:
Nuclear binding energy refers to the energy needed in order to break up the nucleus of an atom into its component parts: protons and neutrons, it is also the energy used up in the formation of the atom.
The difference between the calculated and actual mass of a nucleus gives its mass defect which is used to calculate the binding energy according to Einstein's equation. The mass differences are usually very small, as little as the order of nanograms.
