document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=200908>Question 200908</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The half life of cobalt-60 is 5.3 years.<BR>\n" );
document.write( "a.) find its decay rate<BR>\n" );
document.write( "b.) If you initially have 15 grams of this material, how long until only 10 grams remain?\r<BR>\n" );
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document.write( "I am having trouble can someone help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #151226 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=151226\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Remember,  x = x(0) * 2^(-t/h),,,,where x(0) is  initial  amount  at t=0,,t=time(yrs),   and h = half  life (yrs)<BR>\n" );
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document.write( "x = x(0) *2^(-t/5.3),,,,,,,(a)<BR>\n" );
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document.write( "subst  in given  values<BR>\n" );
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document.write( "10 = 15 *2^( - t/5.3)<BR>\n" );
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document.write( "10/15 =2/3 = 2^(-t/5.3)<BR>\n" );
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document.write( "take  log  both  sides,,,,,remember log (a^b)  = b(loga)<BR>\n" );
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document.write( "log (2/3) = log (2^(-t/5.3) ) = (-t/5.3)log2<BR>\n" );
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document.write( "log(2/3) / log2  = (-t/5.3)<BR>\n" );
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document.write( "-.585 = - t/5.3<BR>\n" );
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document.write( "3.10 = t,,,,,,,,,,(b)<BR>\n" );
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document.write( "check<BR>\n" );
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document.write( "10 = 15 *2^(-3.1/5.3) =10,,,,,,ok<BR>\n" );
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