Answer:


The sample variance would be given by;

And replacing we got:

The standard deviation would be:

Explanation:
For this case we have the following data:
42 40 39 31 22 18 15 12 11.7 10.5
If we sort the values on increasing order we got:
10.5 11.7 12.0 15.0 18.0 22.0 31.0 39.0 40.0 42.0
The range is defined as:


The sample variance would be given by;

And replacing we got:

The standard deviation would be:
