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yawa3891 [41]
3 years ago
6

If a radioactive substance's half-life is 20 years, how much of a 40-gram sample will be left after 60 years? A. 5 grams B. 10 g

rams C. 20 grams D. 30 grams
Biology
2 answers:
satela [25.4K]3 years ago
8 0

Answer:

c. 20

Explanation:

tatiyna3 years ago
6 0
60 years is three half life for the substance, so 40*1/2^3=5
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