K and R cannot serve on any panel unless they serve together.
Either L or S or both serve on any panel that is formed.
15. Which of the following is a properly constituted arbitration panel, with the chairperson listed first?
(A) S; L, M
(B) K; L, R, T
(C) L; M, N, S
(D) T; K, R, S
(E) K; M, N, R, S
16. If, on a given panel, N must serve as chairperson, the other members of that panel must be which of the following?
(A) M and S
(B) S and T
(C) L, R, and S
(D) L, S, and T
(E) R, S, and T
17. If a new arbitration panel, chaired by S, has been formed from an old panel, chaired by M, merely by replacing a single member of the old panel, which of the following must be the referee who was thus replaced?
(A) K
(B) L
(C) N
(D) R
(E) T
Questions 18-22
M, N, O, P, Q, and R are two sets of triplets, not necessarily in the order given. None of the six is married to a sibling or to someone of the same sex:
Four of the six are male and two are female.
Neither set of triplets contains three siblings of the same sex.
M and P are married to each other.
N is Q's only brother.
18. Who CANNOT be sister and brother?