document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=330713>Question 330713</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have the following question Shown below.  I really need help with it please.  I have tried working it out but don't know if its right.  I tried multiplying 8.3 x 10^13 square feet and 200 feet. then divide by  1.3 x 10^-9 but my answer does not show in my choices for the question. Any help will be greatly appreciated.\r<BR>\n" );
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document.write( "The sahara desert covers about 8.3 x 10^13 square feet.<BR>\n" );
document.write( "The average depth of the sand is 200 ft<BR>\n" );
document.write( "A grain of sand has a volume of approxemately 1.3 x 10^-9\r<BR>\n" );
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document.write( "best estimate of the number of grains of sand in the sahara desert?\r<BR>\n" );
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document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #237090 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=237090\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (8.3 x 10^13)(200) = 1660 x 10^13 = 1.66 x 10^16\r<BR>\n" );
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document.write( "(1.66 x 10^16) / (1.3 x 10^-9) = 1.28 x 10^25 (approx)\r<BR>\n" );
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document.write( "FYI: there may be an issue with significant figures<BR>\n" );
document.write( "___ 200 (no decimal point) has one significant figure<BR>\n" );
document.write( "___ \"technically\" , the answer should have only one significant figure\r<BR>\n" );
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document.write( "also , what are the dimensions for the sand grain volume? ___ there may be a units conversion issue </SPAN>\n" );
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