The answer is O II only.
I: Calculation errors would be considered a valid source of error in a laboratory experiment. If the calculations made during the experiment are incorrect, it can affect the accuracy of the results.
II: Inability to calibrate measuring devices would NOT be considered a valid source of error in a laboratory experiment. Calibrating measuring devices is an essential step in any experiment to ensure that the measurements being taken are accurate. If the measuring devices are not calibrated correctly, the results of the experiment will be invalid.
III: Using the wrong solution for a reaction would be considered a valid source of error in a laboratory experiment. If the wrong solution is used, the results of the experiment may not be accurate.
Therefore, II is the only option that would NOT be considered a valid source of error in a laboratory experiment.
The answer is O II only.
I: Calculation errors would be considered a valid source of error in a laboratory experiment. If the calculations made during the experiment are incorrect, it can affect the accuracy of the results.
II: Inability to calibrate measuring devices would NOT be considered a valid source of error in a laboratory experiment. Calibrating measuring devices is an essential step in any experiment to ensure that the measurements being taken are accurate. If the measuring devices are not calibrated correctly, the results of the experiment will be invalid.
III: Using the wrong solution for a reaction would be considered a valid source of error in a laboratory experiment. If the wrong solution is used, the results of the experiment may not be accurate.
Therefore, II is the only option that would NOT be considered a valid source of error in a laboratory experiment.