document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=924217>Question 924217</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me with this?\r<BR>\n" );
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document.write( "The amount of radioactive material, in grams, present after t days is modeled by: <BR>\n" );
document.write( "A(t)=600e^-0.5t\r<BR>\n" );
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document.write( "a) Find the amount present after 12 days. <BR>\n" );
document.write( "I think I got this one. \r<BR>\n" );
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document.write( "A(12)=600e^-0.5*12<BR>\n" );
document.write( "A(12)=1.487g\r<BR>\n" );
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document.write( "b)find the half-life of the material<BR>\n" );
document.write( "This one I had more trouble with. I got a negative answer when I tried it. \r<BR>\n" );
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document.write( "300=600e^-0.5t<BR>\n" );
document.write( ".5=e^-0.5t<BR>\n" );
document.write( "log base e (.5)=-0.5t<BR>\n" );
document.write( "t=(log base e (.5))/-0.5<BR>\n" );
document.write( "t=-.434yrs\r<BR>\n" );
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document.write( "but that doesn't feel right... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #560692 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=560692\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "a) Find the amount present after <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12 ALIGN=MIDDLE  ALT=\"12\"   DISABLED_style= \"max-width:90%; height:auto;\" > days. <BR>\n" );
document.write( "I think I got this one. \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2812%29=600e%5E%28-0.5%2A12%29 ALIGN=MIDDLE  ALT=\"A%2812%29=600e%5E%28-0.5%2A12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2812%29=1.487g ALIGN=MIDDLE  ALT=\"A%2812%29=1.487g\"   DISABLED_style= \"max-width:90%; height:auto;\" >----you got this one\r<BR>\n" );
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document.write( "b)find the half-life of the material<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=300=600e%5E%28-0.5t%29 ALIGN=MIDDLE  ALT=\"300=600e%5E%28-0.5t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=300%2F600=e%5E%28-0.5t%29 ALIGN=MIDDLE  ALT=\"300%2F600=e%5E%28-0.5t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.5=e%5E%28-0.5t%29 ALIGN=MIDDLE  ALT=\".5=e%5E%28-0.5t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28.5%29=ln%28e%5E%28-0.5t%29%29 ALIGN=MIDDLE  ALT=\"ln%28.5%29=ln%28e%5E%28-0.5t%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28.5%29=%28-0.5t%29ln%28e%29 ALIGN=MIDDLE  ALT=\"ln%28.5%29=%28-0.5t%29ln%28e%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >......<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28e%29=1 ALIGN=MIDDLE  ALT=\"ln%28e%29=1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28.5%29=-0.5t ALIGN=MIDDLE  ALT=\"ln%28.5%29=-0.5t\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-0.693147=-0.5t ALIGN=MIDDLE  ALT=\"-0.693147=-0.5t\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-0.693147%2F-0.5=t ALIGN=MIDDLE  ALT=\"-0.693147%2F-0.5=t\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=1.386294 ALIGN=MIDDLE  ALT=\"t=1.386294\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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