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【单选题】
设关系数据库中一个表S的结构为：S（SN，CN，grade），其中SN为学生名，CN为课程名，二者均为字符型；grade为成绩，数值型，取值范围0－100。若要更正的化学成绩为85分，则可用（ ） 。A.
UPDATE S SET grade＝85 WHERE SN＝’’ AND CN＝’化学’
B.
UPDATE S SET grade＝’85’ WHERE SN＝’’ AND CN＝’化学’
C.
UPDATE grade＝85 WHERE SN＝’’ AND CN＝’化学’
D.
UPDATE grade＝’85’ WHERE SN＝’’ AND CN＝’化学’
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【单选题】{ 实现两台三相笼型异步电动机的顺序起动控制,能使用的接触器触点有哪些? (1)动合主触点 (2)动断主触点 (3)自锁触点 (4)动断辅助触点 (5)动合辅助触点 }
A.
(1),(2),(3), (4), (5)
B.
(1),(2), (4)
C.
(1),(3), (4)
D.
(1),(3), (5)
【单选题】听力原文：M:So, Rebecca, what did you do for spring break? W:I went to southern California. I was in Los Angeles and San Diego. Oh, and I stopped in San Juan Capistrano. That'ssouth of Los Angeles and nort...
A.
North of Los Angeles.
B.
Between Los Angeles and San Diego.
C.
East of San Diego.
D.
Los Angeles.
【单选题】听力原文：M: So, Rebecca, what did you do for spring break7 F: I went to southern California. I was in Los Angeles and San Diego. Oh, and I stopped in San Juan Capistrano. That’s south of Los Angeles and n...
A.
North of Los Angeles.
B.
Between Los Angeles and San Diego.
C.
East of San Diego.
D.
Los Angeles
【单选题】听力原文：M: So, Rebecca, what did you do for spring break? F: I went to southern California. I was in Los Angeles and San Diego. Oh, and I stopped in San Juan Capistrano. That's south of Los Angeles and n...
A.
North of Los Angeles.
B.
Between Los Angeles and San Diego.
C.
East of San Diego.
D.
Los Angeles
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