Q$.2($a$)$ Differentiate between $($any three$)$

$($i$)$ Weak and Strong Entity in ER Diagram

$($ii$)$ Primary Key and Foreign Key in SQL

$($iii$)$ Label and Text Control in Visual Basic

$($iv$)$ ER Diagram and EER Diagram$-$

$($y$)$ Database Administrator and Database User

$($b$)($i$)$ Consider the following schema:

Borrower $($Customer$\_$Name, Loan$\_$Number$)$

Loan $($Loan$\_$Number, Branch, Amount$)$

Write Relational Algebra query to find the Customer name who have a loan in all branches.

$($ii$)$ Consider the following schema:

Suppliers$($sid: integer, sname: string, address: string$)$

Parts$($pid: integer, pname: string, color: string$)$

Catalog$($sid: integer, pid: integer, cost: real$)$

Write Relational Algebra query to find the pids of the least expensive parts supplied by supplier

named 'Ajay'.