Answer:
39.02 amu
Explanation:
The average atomic mass of an element can be calculated as follows :

So, the atomic mass of the element X is 39.02 amu.
Iodine is I2 (subscript)
Iodide ion is I-
The answer is D because there is no forces of attraction or repulsion between gas particles .
A cofactor is an organic or inorganic molecule or ion necessary for proper functioning of some biological catalysts (option E).
<h3>What is a cofactor?</h3>
A cofactor in biochemistry is a molecule that binds to and regulates the activity of a protein.
A cofactor is a metal or coenzyme responsible for the functioning of an enzyme and must be present.
Therefore, a cofactor is an organic or inorganic molecule or ion necessary for proper functioning of some biological catalysts.
Learn more about cofactors at: brainly.com/question/13004767
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