I don\'t know how to solve the relational algebra questions.
Deposit (Branch, Acc-No, Cust-Name, Balance) Loan (Branch, Loan-No, Cust-Name, Bala
This is the answer I came up with:
π Branch, Cust-Name, Balance, Acc-No, (σ Balance < 100^branch=”Romford” (Deposit)) ∪ π Branch, Cust-Name, Balance, Loan-No, (σ Balance > 2500 ^branch=”Romford”(Loan))