document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1006251>Question 1006251</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The percent l(x)of the original intensity of light striking the surface of a lake that is available x feet below the surface of the lake is given by the equation <BR>\n" );
document.write( "l(x) = 100e^&#8722;0.95x.\r<BR>\n" );
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document.write( "(a) What percentage of the light, to the nearest tenth of a percent, is available 4 feet below the surface of the lake? <BR>\n" );
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document.write( " % \r<BR>\n" );
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document.write( "(b) At what depth, to the nearest hundredth of a foot, is the intensity of the light one-half the intensity at the surface? <BR>\n" );
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document.write( " ft </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #622405 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=622405\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> L(x)=100e^(-3.8) at 4 feet.<BR>\n" );
document.write( "This is 2.2%<BR>\n" );
document.write( "I want 50% or 50=100e^(-0.95x)<BR>\n" );
document.write( "0.5=e^(-0.95x)<BR>\n" );
document.write( "ln of both sides<BR>\n" );
document.write( "-0.693=-0.95 x<BR>\n" );
document.write( "At 0.73 feet, dividing both sides by -0.95.\r<BR>\n" );
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