A work measurement analyst took 10 observations of a high-production, 3-element based job. The average cycle time for each element is 0.40, 0.50, 0.85 minutes, respectively, and the standard deviation for element 1, 2, and 3 of this job are 0.16, 0.24, and 0.22 minutes, respectively. What would be the necessary sample size (i.e., number of cycles) to have a tolerance of 10%? Assume 95% confidence. Use the t distribution table.