document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1128514>Question 1128514</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The rate at which water evaporates from a certain reservoir depends on the air temperature. The table below shows the number of acre-feet (af) of water per day that evaporates from the reservoir for various temperatures in degrees Fahrenheit.<BR>\n" );
document.write( "Temperature (°F)	(af)<BR>\n" );
document.write( "40	880<BR>\n" );
document.write( "60	1720<BR>\n" );
document.write( "70	2140<BR>\n" );
document.write( "85	2770<BR>\n" );
document.write( "(a) Find a linear model for the number of acre-feet of water that evaporates as a function of temperature. <BR>\n" );
document.write( "E(T) =<BR>\n" );
document.write( "(b) Explain the meaning of the slope of this line in the context of this problem.<BR>\n" );
document.write( "The value of the slope means that an additional _______ af evaporates for a 1°F  increase//decrease? in temperature.<BR>\n" );
document.write( "(c) Assuming that water continues to evaporate at the same rate, how many acre-feet of water will evaporate per day when the temperature is 75°F? _____af </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #745004 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=745004\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The slope between any pair of adjacent numbers is 840/20=42<BR>\n" );
document.write( "point slope formula is y-y1=m(x-x1) m slope and (x1, y1) point<BR>\n" );
document.write( "y-880=42(x-40)<BR>\n" );
document.write( "y-880=42x-1680<BR>\n" );
document.write( "y=42x-800\r<BR>\n" );
document.write( "\n" );
document.write( "the slope is the number of acre feet that evaporate for each increase in temperature of 1 degree F.<BR>\n" );
document.write( "When the temp is 75 degrees, number of AF evaporating is 75*42-800=2350 AF </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );