1. Please answer the questions a)-g) based on the following stem-and-leaf diagram.

1 359

2 166888

3 2467899

4 578

5 366

6 59

1. (a)What percentage of the data are within two standard deviations of the mean?
2. (b)Using interpolation method find 60 percentile for the data set?
3. (c)Whether this data set skewed?
4. (d)Using box-plot criterion to find whether there are outliers. How high would a number to be an outlier for this data set? (please sketch a box and whisker plot or named as box-plot)
5. (e)Could this data set be described by Empirical Rule?
6. (f)Find the coefficient of variation of the data set (Define as).
7. (g)How many numbers have z-scores bigger than 1.5 or smaller than -1.5?