document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=898293>Question 898293</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ok so I have an exponential and log functions activity and I am stuck on 1 problem.\r<BR>\n" );
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document.write( "I did the first question but I am a little confused on the second one.\r<BR>\n" );
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document.write( "Here is some background info for the activity.\r<BR>\n" );
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document.write( "Exponential functions can be used to model the concentration of a drug in a patient's body. Suppose the concentration of Drug X in a patient's bloodstream is modeled by, \r<BR>\n" );
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document.write( "C (t) = C0 e - rt,\r<BR>\n" );
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document.write( "where C (t) represents the concentration at time t (in hours), C0 is the concentration of the drug in the blood immediately after injection, and r > 0 is a constant indicating the removal of the drug by the body through metabolism and/or excretion. The rate constant r has units of 1/time (1/hr). It is important to note that this model assumes that the blood concentration of the drug (C0 ) peaks immediately when the drug is injected.\r<BR>\n" );
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document.write( "1) suppose the drug has a removal rate constant of r = 0.080 1/hr and an initial concentration (Co) of 5.0 mg/L. Find the drug concentration after 4.0 hours using C(t) = Co e^-rt,.\r<BR>\n" );
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document.write( "  I got C(4) = 5e ^ (-0.08)(4) = 3.6 mg/L\r<BR>\n" );
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document.write( "The second question asks \r<BR>\n" );
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document.write( "2) what percent of the drug is left in the body after this time? Use units of measure.\r<BR>\n" );
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document.write( "   would it be the previous answer in percent form?\r<BR>\n" );
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document.write( "thanks so much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #544775 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=544775\">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=C%28t%29 ALIGN=MIDDLE  ALT=\"C%28t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > is in milligrams per liter.  This is not PERCENT, but instead a measure of mass of the drug in 1 liter (of the patient's blood).\r<BR>\n" );
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document.write( "Question Number 2 then is asking for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28C%284%29%2FC%280%29%29%2A100 ALIGN=MIDDLE  ALT=\"%28C%284%29%2FC%280%29%29%2A100\"   DISABLED_style= \"max-width:90%; height:auto;\" >;\r<BR>\n" );
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document.write( "In more specific values,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283.6%2F5.0%29%2A100 ALIGN=MIDDLE  ALT=\"%283.6%2F5.0%29%2A100\"   DISABLED_style= \"max-width:90%; height:auto;\" >  percent. </SPAN>\n" );
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