A radioactive isotope has a half-life of one week. At the end of two weeks the amount remaining is

1) none,
2) one-eighth,
3) one-quarter,
4) one-half,

and at the end of three weeks the amount remaining is
5) none.
6) one-eighth.
7) one-quarter.
8) one-half.


Answer: 3, 6

Physics & Space Science

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Fill in the blank(s) with correct word

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