Three Randomly Chosen Fourteen-Year-Old Junior High Students Who Had Not

Three randomly chosen fourteen-year-old junior high students who had not yet taken driver's education classes were given the written part of the Michigan Driver's Exam. Each student was graded as passing (P) or failing (F) the written exam.
a.Describe the sample space; that is, list all possible combinations of the three students' grades.
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b.Assuming each combination in part (a) is equally likely, what is the probability all three students fail?
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c.Assuming each combination in part (a) is equally likely, what is the probability at least one student passes the written test?
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d.Assuming each combination in part (a) is equally likely, and if you knew at least one student passed the test, what is the probability all three students passed the test?
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