document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=163533>Question 163533</A>: <I><SPAN STYLE=\"word-break: break-all;\"> can someone please help me with this problem:\r<BR>\n" );
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document.write( "A certain radioactive isotope decays at a rate of 0.25% annually. Determine the half - life of this isotope, to the nearest year.\r<BR>\n" );
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document.write( "a. 120 years<BR>\n" );
document.write( "b. 277 years<BR>\n" );
document.write( "c. 200 years<BR>\n" );
document.write( "d. 3 years </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #120479 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=120479\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The isotope follows this power law as a function of time,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28t%29=N%5B0%5D%28.9975%29%5Et ALIGN=MIDDLE  ALT=\"N%28t%29=N%5B0%5D%28.9975%29%5Et\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where t is measured in years and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%5B0%5D ALIGN=MIDDLE  ALT=\"N%5B0%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the initial amount of the isotope.<BR>\n" );
document.write( "Half life is when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28t%29=%281%2F2%29N%5B0%5D ALIGN=MIDDLE  ALT=\"N%28t%29=%281%2F2%29N%5B0%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29N%5B0%5D=N%5B0%5D%280.9975%29%5Et ALIGN=MIDDLE  ALT=\"%281%2F2%29N%5B0%5D=N%5B0%5D%280.9975%29%5Et\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%280.5%29=%280.9975%29%5Et ALIGN=MIDDLE  ALT=\"%280.5%29=%280.9975%29%5Et\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=log%280.9975%2C0.5%29 ALIGN=MIDDLE  ALT=\"t=log%280.9975%2C0.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=276.9 ALIGN=MIDDLE  ALT=\"t=276.9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
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document.write( "Looks like b) 277 years is the closest answer. </SPAN>\n" );
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