a) Given the authorization table, write SQL to grant access rights to each user. Privilege on Product Table Read Insert Modify Delete Grant Liza NO YES NO YES NO Users Steven YES NO YES YES William YES YES YES YES YES (11 marks) b) Consider the interleaved transaction schedule below which suffers from a concurrency control problem: Time Transaction1 Transaction2 Balance(X) begin_transaction 1 2 3 4 5 6 7 8 9 read(X) X=X*2 begin_transaction write(X) read(X) X=X+ 20 write(X) commit que [***] rollback 100 100 100 200 200 200 220 220 100 Assess the schedule above. Identify, name and descibe the problem affecting it. Suggest a solution to the problem. (10 marks) c) Using an example, explain how vertical or horizontal partitioning can help in optimizing database performance. (4 marks)