In a Gaussian distribution, approximately what fraction of measurements lie within one standard deviation of the mean?

• A. About 95 percent of measurements lie within one standard deviation of the mean
• B. Approximately 68 percent of measurements lie within one standard deviation of the mean
• C. Approximately 99.7 percent lie within one standard deviation of the mean
• D. Half of the measurements lie within one standard deviation of the mean

Answer: (B)