document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=759115>Question 759115</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help please. \r<BR>\n" );
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document.write( "The intensity I of light varies inversely w/ the square of the distance d from the source, expressed in the equation I=k/d^2.  If the instensity is 1/2 of a candela 16ft from the source, what is the constant of proportionality?\r<BR>\n" );
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document.write( "Answer Options:<BR>\n" );
document.write( "A.  2 candela-square-feet<BR>\n" );
document.write( "B.  32 candela-square-feet<BR>\n" );
document.write( "C.  256 candela-square-feet<BR>\n" );
document.write( "D.  128 candela-square-feet </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #461863 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=461863\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  I=k/d^2. If the instensity is 1/2 of a candela 16ft from the source, what is the constant of proportionality? \r<BR>\n" );
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document.write( "solve I = k / d^2 for k by multiplying both sides of = by d^2\r<BR>\n" );
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document.write( "k = I * d^2\r<BR>\n" );
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document.write( "now I = 1/2  and d = 16, soooooooo\r<BR>\n" );
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document.write( "k = 1/2 * 16^2\r<BR>\n" );
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document.write( "k = 1/2 * 256\r<BR>\n" );
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document.write( "k = 128 candela-square-feet\r<BR>\n" );
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document.write( "so the answer is D<BR>\n" );
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