document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1113943>Question 1113943</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The half-life of a particular radioactive isotope is 72 hours.\r<BR>\n" );
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document.write( "Write an equation to relate the mass of radioactive material remaining to time (in hours).\r<BR>\n" );
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document.write( "Starting with 170g, what mass will remain in 3 weeks?\r<BR>\n" );
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document.write( "If after one day (24 hours), a different sample of the material was found to have a mass of 14 mg with a half-life of 12h, what was the initial mass of the sample?\r<BR>\n" );
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document.write( "solve using log if possible </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #728987 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</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=728987\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> -----------------------------------------------------------------------<BR>\n" );
document.write( "The half-life of a particular radioactive isotope is 72 hours. <BR>\n" );
document.write( "Write an equation to relate the mass of radioactive material remaining to time (in hours). <BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=pe%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"y=pe%5E%28-kt%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=ln%28y%29=ln%28p%29%2Bln%28e%5E%28-kt%29%29 ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%29%2Bln%28e%5E%28-kt%29%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=ln%28y%29=ln%28p%29-kt ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%29-kt\"   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%28y%29-ln%28p%29=-kt ALIGN=MIDDLE  ALT=\"ln%28y%29-ln%28p%29=-kt\"   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=kt=ln%28p%29-ln%28y%29 ALIGN=MIDDLE  ALT=\"kt=ln%28p%29-ln%28y%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=k=%281%2Ft%29%28ln%28p%2Fy%29%29 ALIGN=MIDDLE  ALT=\"k=%281%2Ft%29%28ln%28p%2Fy%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "If half life is 72 hours, then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=%281%2F72%29%2Aln%282%29 ALIGN=MIDDLE  ALT=\"k=%281%2F72%29%2Aln%282%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=k=0.009627 ALIGN=MIDDLE  ALT=\"k=0.009627\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "This model then  becomes  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=p%2Ae%5E%28-0.009627t%29%29 ALIGN=MIDDLE  ALT=\"highlight%28y=p%2Ae%5E%28-0.009627t%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "p, initial quantity<BR>\n" );
document.write( "y, final quantity<BR>\n" );
document.write( "t, time in hours\r<BR>\n" );
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document.write( "You can figure the other questions based on that. </SPAN>\n" );
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