document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1133312>Question 1133312</A>: <I><SPAN STYLE=\"word-break: break-all;\"> MEDICINE When doctors prescribe medication, they have to consider the rate at which the body filters a drug from the bloodstream. Suppose it takes the human body 6 days to filter out half of the Flu-B-Gone vaccine. The amount of Flu-B-Gone vaccine remaining in the bloodstream x days after an injection is given by the equation y = 𝑦0(0.5)^(𝑥/6), where 𝑦0 is the initial amount. Suppose a doctor injects a patient with 20 μg (micrograms) of Flu-B-Gone.\r<BR>\n" );
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document.write( "a. How much of the vaccine will remain after 1 day? Round your answer to the nearest tenth.\r<BR>\n" );
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document.write( "b. How much of the vaccine will remain after 12 days? Round your answer to the nearest tenth.\r<BR>\n" );
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document.write( "c. After how many days will the amount of vaccine be less than 1 μg? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #750614 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=750614\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a.  y=20*0.5^(1/6)=17.8 microgm<BR>\n" );
document.write( "b.  y=20*0.5^2=5.00 microgm<BR>\n" );
document.write( "c. 1=20*0.5^(x/6)<BR>\n" );
document.write( "0.05=0.5^(x/6)<BR>\n" );
document.write( "ln both sides<BR>\n" );
document.write( "ln 0.05=(x/6) ln 0.5<BR>\n" );
document.write( "-3=(x/6)*(-0.693)<BR>\n" );
document.write( "4.33=x/6<BR>\n" );
document.write( "x=25.98 or 26.0 days </SPAN>\n" );
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