document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1034021>Question 1034021</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A fossilized leaf contains 12% of its normal amount of carbon 14. How old is the fossil (to the nearest year)? Use 5600 years as the half-life of carbon 14.\r<BR>\n" );
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document.write( "    a. 1031<BR>\n" );
document.write( "    b. 17,099<BR>\n" );
document.write( "    c. 20,040<BR>\n" );
document.write( "    d. 36,108<BR>\n" );
document.write( "  \r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #648615 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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/cgi-bin/show-face.mpl?user=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=648615\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We use<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%28t%29+=+A%5B0%5D%281%2F2%29%5E%28t%2F5600%29 ALIGN=MIDDLE  ALT=\"A%28t%29+=+A%5B0%5D%281%2F2%29%5E%28t%2F5600%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Here <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%28t%29+=+.12%2AA%5B0%5D ALIGN=MIDDLE  ALT=\"A%28t%29+=+.12%2AA%5B0%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so we find t...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.12A%5B0%5D+=+A%5B0%5D%281%2F2%29%5E%28t%2F5600%29 ALIGN=MIDDLE  ALT=\".12A%5B0%5D+=+A%5B0%5D%281%2F2%29%5E%28t%2F5600%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.12+=+%281%2F2%29%5E%28t%2F5600%29 ALIGN=MIDDLE  ALT=\".12+=+%281%2F2%29%5E%28t%2F5600%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and, taking the log we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2F5600+=+%28ln+.12%29%2F%28ln+.5%29 ALIGN=MIDDLE  ALT=\"t%2F5600+=+%28ln+.12%29%2F%28ln+.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so that<BR>\n" );
document.write( "t = 17130 years<BR>\n" );
document.write( "The best choice is B. </SPAN>\n" );
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