The data below reflect the number of vacation days that a sample of employees at a certain company have left to take before the end of the year. Complete parts a through c. 11 7 2 3 10 7 9 a. Compute the range for these sample data. The range is b. Compute the variance for these sample data. The variance is nothing. (Round to two decimal places as needed.) c. Compute the standard deviation for these sample data. The standard deviation is nothing. (Round to two decimal places as needed.)