document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=460520>Question 460520</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Strontium-90 has a half-life of 28 years. If a 2.10 mg sample was stored for 180 years, what mass of Sr-90 would remain?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #315865 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=315865\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Strontium-90 has a half-life of 28 years.<BR>\n" );
document.write( " If a 2.10 mg sample was stored for 180 years, what mass of Sr-90 would remain?<BR>\n" );
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document.write( "The radioactive decay formula: <BR>\n" );
document.write( "A = Ao*2^(-t/h)<BR>\n" );
document.write( "where<BR>\n" );
document.write( "A = resulting amt after t yrs<BR>\n" );
document.write( "Ao = initial amt<BR>\n" );
document.write( "t = time in yrs<BR>\n" );
document.write( "h = half-life of substance<BR>\n" );
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document.write( "A = 2.1*2^(-180/28)<BR>\n" );
document.write( "you can do this just as it is on a good calc<BR>\n" );
document.write( "A = .02438 mg remain after 180 yrs  </SPAN>\n" );
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