a) For the existing Blackboard system, a system utilized by the students in order to interact with the virtual classrooms, grades, messages, announcements, and so on, develop ONE UML Use Case diagram for the student user who is uploading the document to Blackboard.
b) For the existing Blackboard system, a system utilized for virtual classroom, grades, messages, and announcements, develop ONE UML Sequence Diagram for uploading the document to Blackboard.