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4.

I think this is correct NSS

The mean  is 28.3

The SD is  9.93

So....two SDs above the mean  is 28.3 * 2(9.3)  = 46.9

And two SDs below the mean is  28.3  - 2(9.3)  =  9.7

So...

16  is the minimum value   and 40  is the max value

So...all   values fall within  2 SDs  from the mean

3

The Mean  is  111.16

The SD  is  32.8

The minimum value is 69

The max value is 158

So  

Two SDs  above the mean  is   111.16 + 2(32.8)   = 176.76

Two SDs  below the mean is  111.16  - 2(32.8)  = 45.56

So  all the values fall within 2SDs  from the mean