The paper referenced in Exercise 4.25 also gave summary quantities for sodium content (in milligrams per kilogram) of chocolate pudding made from instant mix:

2297

2401

2510

2682

2824

3068

3099

3112

3700

3959

a. Compute the mean, the standard deviation, and the interquartile range for sodium content of these chocolate puddings.

I can compute the mean and the interquartile range but how do you find the standard deviation?