Use the Following to Answer the Question(s) Below

Multiple Choice

Use the following to answer the question(s) below.
IT staff for a large corporation has developed the following probability distribution for the number of calls requiring troubleshooting problems per day.

-The standard deviation of the number of calls per day is

A) 1.31.
B) 1.14.
C) 2.77.
D) 1.56.
E) 1.21.