Answer each of the following questions briefly. The questions are based on the following relational

schema:

eid: char$(8),$ ename: char$(20),$ age: integer, salary: real$)$

did: char$(8),$ dname: char$(30),$ budget: real, manager: char$(8)$ Work$($eid:

char$(8),$ did: char$(8),$ pct time: real$)$

a$)$ Assume that an employee works in one or more departments. Write the SQL statement required to

create the Work relation, including appropriate versions of primary and foreign key integrity

constraints, such that when an employee is deleted all his$/$her work records are also removed, and

the deletion of a department is disallowed if there are one or more employees working in the

department.

b$)$ Write the SQL statement to create the Emp relation, and write an SQL statement to add John as an

employee with eid $=101,$ age $=32,$ and salary $=15000.$

c$)$ Write the SQL statement to create the Dept relation such that every department is guaranteed to

have a manager $($represented by manager$)$ and the manager must be an existing employee.