Question 1159085
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4 days ago the amount of Palladium-100 was 10 mg;


8 days ago the amount of Palladium-100 was 20 mg;


12 days ago the amount of Palladium-100 was 40 mg;


16 days ago the mount of Palladium-100 was 80 mg.


<U>ANSWER</U>. Initial mass of Palladium-100 was 80 mg.
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Solved.