What procedural differences between recommended practice and student usage do you think would result in a student's data not supporting this statement?

When there is difference in accuracy between the pipet and the buret, the student's data will not support the statement.

Explanation:

It is a fact that a pipet gives more accuracy than a buret. However based on the experiment the pipet gave more relative error than the buret . In case of pipet the relative error was 0.702% but in case of buret the relative error was 0.511%. This change in relative error occurred as the pipet was not clean perfectly. The pipet should give accurate result than the buret because in the experiment it was said to use pipet but in case of buret an approximate result would come.

If the student is unable to follow the procedure or uses uncleaned apparatus or takes wrong amount of liquid the result that would come out would be wrong.

answer; ///the declaration of independence;

a would be the answer