Uncertainty in the density from the ruler measurements. QUESTIONS: 1. In this experiment you were required to calculate the percent error, whereas, in the experiment performed last week you were required to calculate the percent difference. Why could we not calculate the percent error for the experiment last week? 2. Provide the resolution, sometimes called the least count, for each of the following instruments: ruler, Vernier Caliper, micrometer, and the digital mass scale. 3. Which one of the four instruments listed above would provide the most accurate result when used to measure the thickness of a sheet of paper? Explain why. 4. What is the definition of the zero error, as it applies to the micrometer. How is it possible to account for this error during the experimental measurements? What was the zero error for your group's micrometer that was used during the experiment