更多"What operation on relations R and S"的相关试题:
[单项选择]What operation on relations R and S produces the relation shown below { tuple | tuple∈R ∨ tuple∈S} ( )
A. union
B. difference
C. intersection
D. division
[单项选择]What dose "education quite often produces surprises" mean
A. Education makes people learn a lot of new things outside the textbooks.
B. Education is more open-ended and all-inclusive.
C. Education knows no bounds.
D. Education is a lifelong process
[单项选择]What does "R. S. V. P" stand for
A. Thank you for your invitation.
B. French words meaning "Goodbye"
C. Will you please reply.
D. Require small visa and passport.
[单项选择]What’s cliche
A. Briefly expressed general truth.
B. Idea or expression that has been too much used and is now out-dated.
C. Popular short saying with words of advice..
D. A group of words whose meaning cannot be predicted from the constituent words.
[单项选择]What can the market do for a person who produces goods
A. it tells him what to produce.
B. It provides him with what he needs.
C. It teaches him how to grow tomatoes.
D. it helps him to save his cost.
[单项选择]What's the woman's problem
[单项选择]What's the doctor's diagnosis
A. She is badly shortsighted.
B. She is far-sighted.
C. She needs no glasses.
D. Her eyes are basically normal.
[单项选择]What's the girl's problem
[单项选择]What's the author's attitude
A. Subjective.
B. Neutral.
C. Pessimistic.
D. Activ