In a study of television ratings, groups of 6 U.S. households are randomly selected. In the accompanying table, the random variable x represents the number of households among 6 that are tuned to 60 Minutes during the time that the show is broadcast (based on data from Nielsen Media Research).

x                            P (x)
0..........................0.539
1..........................0.351
2..........................0.095
3..........................0.014
4..........................0.001
5................................0+
6................................0+

Determine whether or not a probability distribution is given. If a probability distribution is given, find its mean and standard deviation. If a probability distribution is not given, identify the requirements that are not satisfied.