The manager of the commercial mortgage department of a large bank has collected data during the past two years concerning the number of commercial mortgages approved per week. The results from these two years (104 weeks) are as follows:

Number of Commercial
Mortgages Approved                        Frequency
0...........................................................................13
1...........................................................................25
2...........................................................................32
3...........................................................................17
4.............................................................................9
5.............................................................................6
6.............................................................................1
7.............................................................................1

a. Compute the expected number of mortgages approved per week.

b. Compute the standard deviation.

c. What is the probability that there will be more than one commercial mortgage approved in a given week?