58874889879879797fc8755555555555555555555555555555555555555555555511111111111111111111111111111111113333333333333333333222222222222220000000000000000000000000000000000000000000000..................
Answer:
hen the number of neutrons is known and the atomic number of an element is known, it becomes easier to determine the approximate mass number by adding the two.
Explanation:
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