document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=440187>Question 440187</A>: <I><SPAN STYLE=\"word-break: break-all;\">  A rock is propelled upward from the top of a building 80 feet tall at an initial velocity of 136 feet per second. The function that describes the height of the rock in terms of time t is f(t) = - 16t2 + 136t + 80. Determine the time at which the rock reaches its maximum height.  <BR>\n" );
document.write( " A. 8.5 sec  <BR>\n" );
document.write( "B. 4.25 sec  <BR>\n" );
document.write( "C. 3.4 sec  <BR>\n" );
document.write( "D. 6.8 sec  <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 #312435 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><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=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=312435\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 16t2=136t<BR>\n" );
document.write( "2t2=17t<BR>\n" );
document.write( "t=17/2<BR>\n" );
document.write( "The rock will return to its' starting point in 8.5 seconds, therefore, it will reach its apogee (highest point) in half that time, or 4.25 seconds.<BR>\n" );
document.write( "16t2=68t<BR>\n" );
document.write( "t2=4.25t<BR>\n" );
document.write( "t=4.25..<BR>\n" );
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