Three tables listed below show random variables and their probabilities. However, only one of these is actually a probability distribution.

A

B

C

X

P(X)

X

P(X)

X

P(X)

5

0.1

5

0.1

5

0.1

10

0.7

10

0.7

10

0.7

15

0.1

15

0.1

15

0.1

20

0.3

20

0.5

20

0.1

a.Which is it?

(Click to select)

A

B

C

b.Using the correct probability distribution, find the probability thatxis:(Round the final answers to 1 decimal place.)

1.Exactly 10 =2.No more than 10 =3.More than 5 =

c.Compute the mean, variance, and standard deviation of this distribution.(Round the final answers to 2 decimal places.)

1.Mean 2.Variance ²3.Standard deviation