Middle of
time   
interval    Change in velocity     Change in time       Average accel
  (s)            (cm/s)                 (s)               (cm/s*s)
-------------------------------------------------------------------
                                                
 1.00     66.2 -  36.2 =  30.0    1.25  -  0.75   = 0.5       60.0
           2.1     1.5     3.6    0.01     0.01     0.02       9.6




 
 1.50                                                                
                                                                     





 2.00






 2.50






 3.00




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