Complete each of the following sentences by choosing the correct term from the word bank.
Anatom's _____ is equal to the weighted average of the masses of all the naturally occurring isotopes of that clement.

Explanation

To complete the sentence: "An atom's _____ is equal to the weighted average of the masses of all the naturally occurring isotopes of that element," we need to identify the correct term that fits in the blank.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks us to fill in the blank with a term that describes a property of an atom related to its isotopes.

2. **Identifying Key Terms**: The key phrase in the question is "weighted average of the masses of all the naturally occurring isotopes." This suggests that we are looking for a term that relates to the mass of an atom.

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