Strontium-90 Is a Byproduct in Nuclear Reactors Fuelled by the Radioisotope

question 21

Multiple Choice

Strontium-90 is a byproduct in nuclear reactors fuelled by the radioisotope uranium-235. The half-life of strontium-90 is 28.8 y. What percentage of a strontium-90 sample remains after 85.0 y.?

• A) 33.9%
• B) 2.95%
• C) 87.1%
• D) 0.129%
• E) 12.9%

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Definitions:

Flu Vaccine

A vaccine designed to protect against influenza viruses, typically reformulated annually to combat the most common circulating strains.

Test Statistic

A value calculated from sample data during a hypothesis test that is used to determine whether to reject the null hypothesis.

P-value

A measure in statistical hypothesis testing representing the probability of obtaining test results at least as extreme as the results actually observed, under the assumption that the null hypothesis is true.

Test Statistic

A value calculated from sample data that is used in a hypothesis test to decide whether to reject the null hypothesis.