You can't calculate the atomic mass of milk because it's not a single element or molecule.

Here's why:

* Milk is a complex mixture: It contains water, fats, proteins, sugars, vitamins, and minerals. Each of these components is made up of different atoms.

* Atomic mass refers to atoms: It's the average mass of an atom of a specific element.

You could calculate the average molecular weight of milk by considering the proportions of each component and their respective molecular weights. However, that's not the same as atomic mass.