I could use some help understanding the following question and getting a breakdown of steps in how to answer.

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The Computer Systems Department has eight faculty, six of whom are tenured. Dr. Vonder, the chair, wants to establish a committee of three department faculty members to review the curriculum. If she selects the committee at random:

a. What is the probability all members of the committee are tenured?

b. What is the probability that at least one member is not tenured? (Hint: For this question, use the complement rule).