The following table represents the number of free throws a typical NBA player makes in three attempts.

Free Throws Made

0

1

2

3

Probability

0.2

0.3

0.3

What is the probability needed in order to make this a valid probability distribution?

1

0.3

0.1

0

None of the above

What is the mean of this distribution?

1.5

0.25

1.5

0.267

None of the above

What unit of measurement does the standard deviation have?

Square root of free throws

No unit of measurement

Free throws

Free throws squared

None of the above, as it depends on the situation