Let R and S be relational schemas such that R = {a, b, c} and S = {c}. Now consider the following queries on the database:

Let R and S be relational schemas such that R = {a, b, c} and S = {c}.

1.	Let R and S be relational schemas such that R = {a, b, c} and S = {c}. Now consider the following queries on the database:
A.	1 and 2
B.	1 and 3
C.	2 and 4
D.	3 and 4
Answer» D. 3 and 4

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Let R and S be relational schemas such that R = {a, b, c} and S = {c}. Now consider the following queries on the database:

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