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1 year ago

12

the half -life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mas

s. starting with 155 gramsbof a radioactive isotope, how much will be left after 3 half-lives?

1 answer:

SVETLANKA909090 [29]1 year ago

7 0

Answer:

after 3 half lives the amount should be reduced to 19.375g

Step-by-step explanation:

after the first half life , amount left =

155÷2

= 77.5g

2nd half life

77.5÷2

=38.75g

3rd Half life

38.75÷2

=19.375g

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Answer:

0.5 = 50% probability that he or she is not in any of the language classes.

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We treat the number of students in each class as Venn sets.

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