document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=723958>Question 723958</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1. Plutonium has a half life of 24,000 years. Write an equation to represent the percentage of plutonium remaining after t years. P(t)= ________________\r<BR>\n" );
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document.write( "2. The intensity of light below the surface of a particular lake is reduced by 10% for every metre below the surface. Write an exponential equation that models the percent of light left at any depth, x metres below the surface. L(x) =___________________ </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #443555 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=443555\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28t%29=P%5B0%5De%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"P%28t%29=P%5B0%5De%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Find k first, using half life fact.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2=e%5E%28-k%2A24000%29 ALIGN=MIDDLE  ALT=\"1%2F2=e%5E%28-k%2A24000%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%281%2F2%29=-k%2A24000 ALIGN=MIDDLE  ALT=\"ln%281%2F2%29=-k%2A24000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-ln%281%2F2%29%2F24000=k ALIGN=MIDDLE  ALT=\"-ln%281%2F2%29%2F24000=k\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28k=2.888%2A10%5E%28-5%29%29 ALIGN=MIDDLE  ALT=\"highlight%28k=2.888%2A10%5E%28-5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "MODEL: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28P%28t%29=P%5B0%5De%5E%28-2.89%2A10%5E%28-5%29%2At%29%29 ALIGN=MIDDLE  ALT=\"highlight%28P%28t%29=P%5B0%5De%5E%28-2.89%2A10%5E%28-5%29%2At%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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