set output 'falling_ball.ps' 
set term postscript enhanced color 'Helvetica,18'  
set key 1.2,30.0
set xlabel 'Time (seconds) ' 
set ylabel 'Distance (meters) ' 
set title 'A ball dropped from a high window 
plot [0:2][-20:55] (50-0.5*9.8*x*x) t 'height above ground'   with lines lc -1 lw 2   ,  0.0-0.5*9.8*x*x t 'displacement from window'   with lines lc -1 lt 2  lw 2   
set output 
quit 
