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Figure 3 showed that a sand depth of 10cm is better than the larger sand depth of 32cm. Assuming there was no error in the calculations, errors may be occuring during the experiment. Logically, this result did not make sense. In addition, this result did not go according to our prediction that at a larger depth sand, the DO concentration would be higher. Furthermore, the following results in Figures 4 and 5 (below) obtained at a later date showed that a larger sand depth extracted more DO.
Figure 4 The DO Concentration versus Time. The DO Concentration is calculated from the air volume.
Figure 5 The DO Concentration versus Time. The DO Concentration is calculated from the air volume. This graph is the same as Graph 4 except that this graph excludes the results from the flow rate of 150 ml/min for 33 cm sand depth.
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