document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136174>Question 136174</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.Phosphorus-32 is used to study a plant's use of fertilizer. It has a half life of 14.3 days. Write the exponential decay function for a 50-mg sample. Find the amount of phosphorous- 32 remaining after 84 days?<BR>\n" );
document.write( "2. Iodine-131 is used to find leaks in water pipes. It has a half life of 8.14 days. Write the exponential decay function for a 200-mg sample. Find the amount of iodine-131 remaining after 72 days. <BR>\n" );
document.write( "Thank you for helping me kind tutors </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99848 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=99848\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The half-life decay formula:<BR>\n" );
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document.write( "A = Ao * 2^(-t/h)<BR>\n" );
document.write( "Where:<BR>\n" );
document.write( "A = resulting amount after t time<BR>\n" );
document.write( "Ao = initial amount<BR>\n" );
document.write( "t = elapsed time<BR>\n" );
document.write( "h = half-life of the substance<BR>\n" );
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document.write( "1.Phosphorus-32 is used to study a plant's use of fertilizer. It has a half life of 14.3 days. Write the exponential decay function for a 50-mg sample. Find the amount of phosphorous- 32 remaining after 84 days?<BR>\n" );
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document.write( "A = 50 * 2^(-84/14.3)<BR>\n" );
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document.write( "A = 50 * 2^-5.874<BR>\n" );
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document.write( "A = 50 * .017; find 2^-5.874 on a good calculator<BR>\n" );
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document.write( "A = .8525 mg remain after 84 days<BR>\n" );
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document.write( "2. Iodine-131 is used to find leaks in water pipes. It has a half life of 8.14 days. Write the exponential decay function for a 200-mg sample. Find the amount of iodine-131 remaining after 72 day<BR>\n" );
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document.write( "Do this exactly the same way.<BR>\n" );
document.write( "A = 200 * 2^(-72/8.14)<BR>\n" );
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document.write( "Do you have any questions?\r<BR>\n" );
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