document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=334463>Question 334463</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ripples. A pebble is dropped into a calm pond, causing ripples in the form of concentric circles. The radius (in feet) of the outer ripple is given by r(t)=.6t, where t is the time in seconds after the pebble strikes the water. The area of the circle is given by the function A(r) =&#960; * r^2. Find and interpret (A&#9702;r)(t). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #239633 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=239633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A pebble is dropped into a calm pond, causing ripples in the form of concentric circles. The radius (in feet) of the outer ripple is given by r(t)=.6t, where t is the time in seconds after the pebble strikes the water. The area of the circle is given by the function A(r) =&#960; * r^2. Find and interpret (A&#9702;r)(t).<BR>\n" );
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document.write( "(A&#9702;r)(t) = A[0.6t] = (pi)*(0.6t)^2<BR>\n" );
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document.write( "Interpret: (A&#9702;r)(t) gives the area of the circle when the <BR>\n" );
document.write( "radius is 0.6t, where t is the time in seconds after the peblle <BR>\n" );
document.write( "strikes the water.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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