document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=859111>Question 859111</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A person drinks alcohol at a party.  After her last drink, the alcohol level of her blood soon reaches a maximum of 0.28 milligrams alcohol per milliliter of blood.  If the half life of alcohol in her blood is 2 hours, how long must she wait before driving at the legal limit of 0.08 milligrams alcohol per milliliter of blood?\r<BR>\n" );
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document.write( "All I know is that I have to divide something in half, but I don't know what or how to set up the equation.  I think that I would use this equation but I am not sure A=A_0e^rt ?  But I am not sure.\r<BR>\n" );
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document.write( "Thanks in advance for the help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #517742 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=517742\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Half life usually denotes using an equation with (1/2) as the base.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=A%5B0%5D%2A%281%2F2%29%5E%28kt%29 ALIGN=MIDDLE  ALT=\"A=A%5B0%5D%2A%281%2F2%29%5E%28kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%5B0%5D%2F2=A%5B0%5D%2A%281%2F2%29%5E%282k%29 ALIGN=MIDDLE  ALT=\"A%5B0%5D%2F2=A%5B0%5D%2A%281%2F2%29%5E%282k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2=%281%2F2%29%5E%282k%29 ALIGN=MIDDLE  ALT=\"1%2F2=%281%2F2%29%5E%282k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2k=1 ALIGN=MIDDLE  ALT=\"2k=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=1%2F2 ALIGN=MIDDLE  ALT=\"k=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=A%5B0%5D%2A%281%2F2%29%5E%28t%2F2%29 ALIGN=MIDDLE  ALT=\"A=A%5B0%5D%2A%281%2F2%29%5E%28t%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
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