A SELECT statement can be used to perform these three functions: 1. Choose rows from a table. 2. Choose columns from a table 3. Bring together data that is stored in different tables by creating a link between them. Which set of keywords describes these capabilities? （）
A. difference, projection, join
B. selection, projection, join
C. selection, intersection, join
D. intersection, projection, join
E. difference, projection, product
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柴油机前后增压器的冷却水属于高温冷却水系统。
A. 正确
B. 错误
Which of the following is a benefit of the IBM Long Term File System (LTFS)? （）
A. management of the library files
B. management of the encryption keys and archives
C. helps to reduce tape, file management and archive costs
D. helps to control the write speed matching on LTO-4 drive
冷却水系统对柴油机进行冷却，冷却温度越低越好。
A. 正确
B. 错误
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