This is Database relational algebra problem:

10. Find customer-ids who are both depositors as well as borrowers, not necessarily at the same branch

Task-2: Consider the following schema of Bank-Database, and answer questions 6 to 10. branch(branch_name, branch_city, assets) customer (ID, customer_name, customer_street, customer_city) loan (loan_number, branch_name, amount) borrower (ID, loan-number) account (account_number, branch_name, balance) depositor (ID, account_number)