document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=870153>Question 870153</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the half-life of Rubidium-87 is about 48.8 billion years\r<BR>\n" );
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document.write( "A. deterimine the value of k and the equation of decay for rubidium-87 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #524718 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39625)</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=524718\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Starting from <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=I%2Ae%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"A=I%2Ae%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, I for initial amount, A for amount after time t,<BR>\n" );
document.write( "I can be picked arbitrarily as 1, and then A=1/2.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2=1%2Ae%5E%28-k%2A48.8%29 ALIGN=MIDDLE  ALT=\"1%2F2=1%2Ae%5E%28-k%2A48.8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "Solve for k.\r<BR>\n" );
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document.write( "Do you <i>need</i> more help? </SPAN>\n" );
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