Sensitivity Of The Centogram Balance -If the same object was massed several times on the same balance, the normal variation would be within + .02 grams. -For example, an object with a mass of 100.00 grams would range anywhere from 99.98 grams to 100.02 grams. -This is because the balance is only able to detect changes in mass of more than .02 grams. Any change in mass of less than or equal to .02 grams is not a real change in mass. This is due to the normal variation of the balance.   Histograms -A histogram is a type of bar graph that shows how often answers occur. -The height of the bars indicate how many times an answer occurs. -The vertical axis is labeled "frequency" while the horizontal axis is labeled with the type of data found in the class results chart. -The title should indicate the type of data shown and what it was based on.