皮皮学，免费搜题
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【单选题】
有3个关系R、S和T如下: R A B C a 1 2 b 2 1 c 3 1 S A B C d 3 2 c 3 1 T A B C a 1 2 b 2 1 c 3 1 d 3 2 由关系R和S通过运算得到关系T,则所使用的运算是( )。A.
选择
B.
差
C.
笛卡儿积
D.
并
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皮皮学刷刷变学霸
举一反三
【单选题】All else constant, as the market price of a bond increases the current yield _____ and
A.
increases; increases.
B.
increases; decreases.
C.
decreases; decreases.
D.
decreases; increases.
E.
remains constant; increases.
【单选题】I'm going to buy a pair of __________ in a __________ store. [ ]
A.
shoe; shoe
B.
shoes; shoe
C.
shoe; shoes
【单选题】If the expected return on bonds increases, all else equal, the demand for bonds increases, the price of bonds ________, and the interest rate ________.
A.
increases; decreases
B.
increases; increases
C.
decreases; decreases
D.
decreases; increases
【简答题】All visitors are requested to ________ with the regulations. A) comply B) agree C) assist D) consent
【单选题】The_______is just around the corner and you won’t miss it.
A.
shoe’s shop
B.
shoe shop
C.
shoes shop
D.
shoes’ shop
【单选题】Which is the way to the ______? [ ]
A.
shoe factory
B.
shoes factory
C.
shoe's factory
D.
shoes' factory
【单选题】All else constant, as the variable cost per unit increases, the:
A.
contribution margin decreases.
B.
sensitivity to fixed costs decreases.
C.
degree of operating leverage decreases.
D.
operating cash flow increases.
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