document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1200505>Question 1200505</A>: <I><SPAN STYLE=\"word-break: break-all;\"> NASA launches a rocket at t = 0 seconds. Its height, in meters above sea-level, as a function of time is given by h(t)= -4.9t^2 + 196t + 311\r<BR>\n" );
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document.write( "Assuming that the rocket will splash down into the ocean, at what time does splashdown occur?\r<BR>\n" );
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document.write( "The rocket splashes down after [         ] seconds.\r<BR>\n" );
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document.write( "How high above sea-level does the rocket get at its peak?\r<BR>\n" );
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document.write( "The rocket peaks at [             ] meters above sea-level.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #834667 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=834667\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> NASA launches a rocket at t = 0 seconds. Its height, in meters above sea-level, as a function of time is given by h(t)= -4.9t^2 + 196t + 311\r<BR>\n" );
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document.write( "Assuming that the rocket will splash down into the ocean, at what time does splashdown occur?\r<BR>\n" );
document.write( "\n" );
document.write( "The rocket splashes down after [         ] seconds.\r<BR>\n" );
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document.write( "How high above sea-level does the rocket get at its peak?\r<BR>\n" );
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document.write( "The rocket peaks at [             ] meters above sea-level.<BR>\n" );
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document.write( "1st, that's not a rocket, it's a projectile.<BR>\n" );
document.write( "h(t)= -4.9t^2 + 196t + 311<BR>\n" );
document.write( "The max of the parabola is at t - -b/2a = -196/(-4.9*2) = 20 seconds<BR>\n" );
document.write( "h(20) = -4.9*400 + 196*20 + 311 = 2271 meters MSL<BR>\n" );
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document.write( "The rocket splashes down after? seconds.<BR>\n" );
document.write( "s = at^2/2<BR>\n" );
document.write( "2271 = 4.9t^2<BR>\n" );
document.write( "t =~ 21.53 seconds\r<BR>\n" );
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