In a study of families with children with disabilities, group of 5 US households were randomly selected. In the table below, the random variable x represents the number of households among 6 that had a child with a disability living there.

x P(x)

0 0.02

1 0.15

2 0.29

3 0.31

4 0.23

a)Is this a probability distribution?

b)What is the mean?

c)What is the standard deviation?