document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1006602>Question 1006602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this problem:\r<BR>\n" );
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document.write( "A pebble is dropped into a still pool, causing ripples in the form of concentric circles. The radius r of the outer circle is increasing at a rate of 25cm/s. When the radius is 100cm, at what rate is the total area of the disturbed water increasing? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #622730 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=622730\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=pi%2Ar%5E2 ALIGN=MIDDLE  ALT=\"A=pi%2Ar%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "A for area is a function of time t, and so it r for radius.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dA%2Fdt=pi%2A2r%2A%28dr%2Fdt%29 ALIGN=MIDDLE  ALT=\"dA%2Fdt=pi%2A2r%2A%28dr%2Fdt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >,  and Chain Rule is used.\r<BR>\n" );
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document.write( "Description gives  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28dr%2Fdt=25%2Cr=100%2CdA%2Fdt=FindThisValue%29 ALIGN=MIDDLE  ALT=\"system%28dr%2Fdt=25%2Cr=100%2CdA%2Fdt=FindThisValue%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28dA%2Fdt=pi%2A2%2A100%2A25%29 ALIGN=MIDDLE  ALT=\"highlight%28dA%2Fdt=pi%2A2%2A100%2A25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2Api ALIGN=MIDDLE  ALT=\"500%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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