Question I (70 points total) Consider the following relational database for storing data about employees and projects: employee (employee_id, name, annual salary) project (project_name, budget) participates (employee_id, project_name) Assume that (i) each employee is assigned a unique ID, (i) each project is assigned a unique name, (iii) an employee may participate in multiple projects and multiple employees may participate in the same project, and (iv) some employees may not participate in tiny project. (a) (10 points) Define the primary key for each of the above relations. Furthermore, find all foreign keys. For each foreign key, the referencing and referenced relations must be clearly specified. (b) (10 points) Write an expression in SQL to find the IDs of the employees that participate in project 'X', but not project 'Y'. (c) (10 points) Write an expression in SQL to find the total amount of budget to support all projects in which employee '1111' participates. (d) (10 points) Write an expression in SQL to update the annual salary of each employee as follows: If the current annual salary is less than $100,000, increase the salary by 4 percent. Otherwise, increase the salary by 3 percent