average          delta_t                     delta_x
  time         time            change in      pos          change in      avg speed
  (s)          (s)             time (s)      (cm)          pos (cm)          (cm/s)
-------------------------------------------------------------------------------------
0.5 +/- 0.1                                 8.4 +/-  0.8 

             0.75 +/- 0.1     0.5 +/- 0.2                17.7 +/- 0.9      35

1.0 +/- 0.1                                26.1 +/-  0.1 

             1.25 +/- 0.1

1.5 +/- 0.1                                 56 +/-  3   



2.0 +/- 0.1                                104 +/-  3   



2.5 +/- 0.1                                162 +/-  8   



3.0 +/- 0.1                                230 +/- 18   



3.5 +/- 0.1                                308 +/-  5   
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