How many tuples does the result of the following relational algebra expression contain? Assume that the schema of A B is the same as that of A. (A B)A.ld>40 C.ld<15C

How many tuples does the result of the following relational algebra ex

1.	How many tuples does the result of the following relational algebra expression contain? Assume that the schema of A B is the same as that of A. (A B)_{A.ld>40 C.ld<15}C
A.	7
B.	4
C.	5
D.	9
Answer» B. 4

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How many tuples does the result of the following relational algebra expression contain? Assume that the schema of A B is the same as that of A. (A B)A.ld>40 C.ld<15C

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How many tuples does the result of the following relational algebra expression contain? Assume that the schema of A B is the same as that of A.
(A B)_{A.ld>40 C.ld<15}C