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【简答题】
在数列a n 中，已知a 1 =1，a n =2a n-1 +n-2，n∈N * ，n≥2． （1）求证：数列a n +n是等比数列； （2） 求数列 { a n 2 n } 的前n项和为S n ．
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【简答题】For a few minutes he just ______ there. (lie)
【单选题】听力原文：What did Tom do after watching the man for a few minutes? (9)
A.
He thought he was a mad.
B.
He went away.
C.
He helped him with fishing.
D.
He invited him to have a drink together.
【单选题】For a few minutes he tapped the switch after each flash. ( )
A.
(a) touched
B.
(b) painted
C.
(c) pressed
D.
(d) snapped
【单选题】For a few minutes he tapped the switch after each flash.
A.
touched
B.
painted
C.
pressed
D.
snapped
【简答题】He fell into a ditch and lay there, semiconscious , for a few minutes.
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