C. Short-Answer Questions (Total 30 points) Write concise and complete answer for each question. A few sentences or a short paragraph would be sufficient. You may draw diagrams to help you answer the questions if necessary. 1. (10 points) List and describe the three levels of DBMS schema. Which level of schema design is the Entity-Relationship (ER) model used for? 5 points) List at least 3 major functionality of DBMSs and briefly discuss how database systems elp you from your real world experience