If 43.2 mg of a certain radioactive isotope disintegrates to 10.8 mg in 59.6 seconds, what is the half-life of the isotope?
a) 19.9 seconds
b) 25.0 seconds
c) 14.9 seconds
d) 29.8 seconds
e) 59.6 seconds
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If 43.2 mg of a certain radioactive isotope disintegrates to 10.8 mg in 59.6 seconds, what...
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