(Solve this part independently). A random sample of 6 National bank employees was taken to help estimate the average amount of time(x) employees spent per week on their cell phones. The sample data and some relevant information are listed below: 13, 5, 6,10, 7,12. Ex 2 53. Sample Variance ofx = 10.9667 Find an unbiased estimator of the average time per week for all bank employees