document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1126133>Question 1126133</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Radioactive Decay. Strontium-90 has a half-life of 28 years. How long will it take for 40 grams of this to decay to 5 grams? Apply the formula N= N0e^rt, where N is the number of grams.\r<BR>\n" );
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document.write( "Round your answer to the nearest year. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #742500 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39623)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=742500\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Half-life of 28 years given\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Ae%5E%28rt%29=1%2F2 ALIGN=MIDDLE  ALT=\"1%2Ae%5E%28rt%29=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=e%5E%28rt%29=1%2F2 ALIGN=MIDDLE  ALT=\"e%5E%28rt%29=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28e%5E%28rt%29%29=ln%281%2F2%29 ALIGN=MIDDLE  ALT=\"ln%28e%5E%28rt%29%29=ln%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%2At=ln%281%2F2%29 ALIGN=MIDDLE  ALT=\"r%2At=ln%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Your already know that for this, t=28.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=ln%281%2F2%29%2F28 ALIGN=MIDDLE  ALT=\"r=ln%281%2F2%29%2F28\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You should be able to use this for answering the question and using the equation in your given instructions. </SPAN>\n" );
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