Please help me solve this word problem: A certain radioactive element decays at a rate of 4% per year. Find the half-life of the substance (i.e. the time it will take for one half of any given amount of the substance to decay).
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document.write( "Let 
be the original amount\r\n" );
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document.write( "After 1 year only 96% will remain, which will be 
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document.write( "After 2 years only 96% of will remain, which is 
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document.write( "After 3 years only 96% of will remain, which is 
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document.write( "After n years only 96% of 
will remain, which is 
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document.write( "We want to know how many years before what will remain will be only 
or 
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document.write( "Divide both sides by A\r\n" );
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document.write( "Take logs of both sides:\r\n" );
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document.write( "Use the rule of logs that says 
to bring\r\n" );
document.write( "the exponent n in front of the log\r\n" );
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document.write( "Divide both sides by 
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document.write( "or 17 years, rounded to the first whole year that the amount will be\r\n" );
document.write( "no more than half the original amount.\r\n" );
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document.write( "Edwin
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