Compute the expected value for distribution

Question

Discuss the below:

Q1: Given the following probability distributions:

Distribution  A		Distribution B
X                                      P(X)		X                                  P(X)
0	0.50	0	0.05
1	0.20	1	0.10
2	0.15	2	0.15
3	0.10	3	0.20
4	0.05	4	0.50

1. Compute the expected value for each distribution.
2. Compute the standard deviation for each distribution.
3. Compare and contrast the results of distributions A and B.

Q2: The following table contains the probability distribution for the number of traffic accidents daily in a small city.

Number of Accidents Daily (X)	P(X)
0	0.10
1	0.20
2	0.45
3	0.15
4	0.05
5	0.05

1. Compute the mean or expected number of accidents per day.
2. Compute the standard deviation.