document.write( "Question 1048579: Please help me solve this question\r
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\n" ); document.write( "\n" ); document.write( "4. An initial 65 mg sample of a radioactive substance decays to 30 mg in
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\n" ); document.write( "(a) Find the rate of decay of the substance.
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\n" ); document.write( "(c) How long would it take until only 10 mg of the amount remains?
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Algebra.Com's Answer #664180 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
This demonstration and lesson should be all the help you need:
\n" ); document.write( "exponential decay - a video lesson
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