When aboveground nuclear tests were conducted, the explosions shot radioactive dust into the upper atmosphere. Global air circulations then spread the dust worldwide before it settled out on ground and water. One such test was conducted in October 1976. What fraction of the WSr produced by that explosion still existed in October 2006? The half-life of ""^(90)Sr is 29 y.

When aboveground nuclear tests were conducted, the explosions shot rad

1.	When aboveground nuclear tests were conducted, the explosions shot radioactive dust into the upper atmosphere. Global air circulations then spread the dust worldwide before it settled out on ground and water. One such test was conducted in October 1976. What fraction of the WSr produced by that explosion still existed in October 2006? The half-life of ""^(90)Sr is 29 y.
Answer» ANSWER :0.49

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