It's extremely Urgent !! . please I need their answers now

4. There is an authorization-grant graph for users (U1,U2,U3,U4,U5), their grant relationships are as following, their privileges have been granted in cascade mode, after execute the statement: REVOKE DELETE ON department FROM U3, who will LOSE the privilege of deleting items on table department? Page 1/Total 6 pages A. U1,U3,U5 B. U3,U5 C. U2,U4 D. U4,U5 5. On schema R(A1,A2,A3,A4,A5), if functional dependencies (A3,A2)A1, (A1,A5)A4 hold, the candidate key of R is: A. (A1,A5) B.(A1,A2,A3,A5) C.(A3,A2,A5) D. (A1,A2,A3) 6. If a DB user wants to remove all tuples from a certain relation in the database but keep its structure, which SQL statement can be used:( ) A. insert into B.drop table C. delete from D. select-from-where 7. In SQL language, Grant and Revoke statements are used to keep the ( ) of database. A. consistency B.integrity C.reliability D. security 8. Given a schema R(A,B,C,D), multi-valued dependency ABC holds on R, according to the following tuples in r(R), which tuple must be in this relation? A. (3,2,1,3) B. (3,2,2,1) C. (3,2,1,2) D. (3,2,3,4) 9. In terms of ER model, which of the following statements is true?( ) A. ER model is applied in the physical-design phase, it provides data organization on the physical storage. B. The E-R data model consists two basic concepts: entity sets, and attributes. C. Participation Constraints of ER model must be one of 1-1, many-1, many-many. D. Every weak entity must be associated with an identifying entity. 10. Which of the following operation can not be performed on views? ( ) A. Update views B. query views B. create a new table on a view D. create a new view on a view 11. Refer to the account table, which tuple is in the result for the following SQL statement: Page 2/Total 6 pages SELECT COUNT (*), account_type FROM accounts WHERE balance 1; A.(DirectDebit,362.74)B.(1,Credit)C.(2,DirectDebit)D.(16227,On-LineSaver) 12. There are X tuples in relation R1(B,C,D,E,F), Y tuples in relation R2(A,B,C,D),so the max number of all tuples and max columns in R1 inner join R2 may be: ( ) A. Max(X,Y),6 B. XY,9 C. XY,6 D. Max(X,Y),9 13. How many tuples would be returned if the following queries are executed on the table takes(ID. course id. sec id. semester. vear) 1) SELECT count () FROM takes WHERE year