GRE数学：网络课堂逻辑笔记（6）.

　　Passage 6

　　Two male singers, P and S; two female singers, R and V; two male comedians, T and W; and two female comedians, Q and U, are the eight entertainers who are to perform at the Stuart heater on a certain night. Each entertainer is to perform alone and only once that night. The entertainers may perform in any order that conforms to the following restrictions:

　　The performances by singers and the performances by comedians must alternate throughout the evening.

　　The first performance that evening must be by a female entertainer, and the second performance by a male entertainer.

　　The final performance must be by a male singer.

　　1. Which of the following could be the last of the entertainers to perform?

　　(A) R (B) S (C) T (D) V (E) W

　　2. Which of the following could be the first of the entertainers to perform?

　　(A) P (B) R (C) U (D) V (E) W

　　3. If R is to perform fourth, which of the following must perform sixth?

　　(A) P (B) S (C) U (D) V (E) W

　　4. If U is to perform seventh, which of the following must perform first?

　　(A) Q (B) R (C) S (D) T (E) V

　　5. If P is to perform eighth, which of the following must perform second?

　　(A) R (B) S (C) T (D) V (E) W

　　6. If T is to perform third, W must perform

　　(A) first or fifth (B) second or fifth

　　(C) fourth or seventh (D) fifth or seventh

　　(E) sixth or seventh

　　7. If Q is to perform third, V fourth, and W fifth, which of the following must perform sixth?

　　(A) P (B) R (C) S (D) T (E) U

　　keys:

　　passage 1: 1.E 2.A 3.C 4.A 5.C

　　passage 2: 1.A 2.E 3.B 4.E 5.C

　　passage 3: 1.D 2.E 3.A 4.C 5.D

　　passage 4: 1.D 2.C 3.E

　　passage 5: 1.A 2.A 3.D 4.E

　　passage 6: 1.B 2.C 3.D 4.A 5.B 6.D 7.B