Suppose a given user view contains information about employees and projects. Suppose further each employee has a unique EmployeeNum and each project has a unique ProjectNum. Explain how you would implement the relationship between employees and projects in each of the following scenarios:
a. Many employees can work on a given project, but each employee can work on only a single project.
b. An employee can work on many projects, but each project has a unique employee assigned to it.
c. An employee can work on many projects, and a project can be worked on by many employees.