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Answer:
139.13
Explanation:
The average atomic mass of the element Likhitium is the sum of the relative abundance of all the isotopes of Likhitium.
We obtain the relative atomic mass of Likhitium as follows;
(44.7/100 * 138) + (52.3/100 * 139) + (0.5/100 * 140) + (2.5/100 * 141)
61.7 + 73.2 + 0.7 + 3.53 = 139.13
Hence the relative abundance of Likhitium is 139.13
