document.write( "Question 1088827: After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1988​, the hay in that country was contaminated by a radioactive isotope​ (half-life 6 ​days). If it is safe to feed the hay to cows when 14​% of the radioactive isotope​ remains, how long did the farmers need to wait to use this​ hay?\r
\n" ); document.write( "\n" ); document.write( "The farmers needed to wait approximately
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\n" ); document.write( "​(Round to one decimal place as​ needed.)
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Algebra.Com's Answer #703150 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Exponential Decay,
\n" ); document.write( "just the beginning,
\n" ); document.write( "\"y=p%2Ae%5E%28-kx%29\"
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\n" ); document.write( "\"1%2F2=1%2Ae%5E%28-6k%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"ln%281%2F2%29=-6k\"\r
\n" ); document.write( "\n" ); document.write( "\"-6k=-ln%282%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=ln%282%29%2F6\"\r
\n" ); document.write( "\n" ); document.write( "\"k=0.1155\"\r
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\n" ); document.write( "\n" ); document.write( "MODEL, \"y=p%2Ae%5E%28-0.1155x%29\";\r
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\n" ); document.write( "\n" ); document.write( "If x is time since initial release, IN DAYS, and p=1, and y=0.14, then solve for x.
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