1. A common practice is to create a(n) _____ on any field that is used as a search key, in comparison operations in a conditional expression, or when a user wants to list rows in a specific order. 2. A table can be deleted from the database by using the _____ TABLE command. a. MODIFY b. DROP c. ERASE d. DELETE 3. SQL requires the use of the _____ command to enter data into a table. a. NOT NULL b. SELECT c. INSERT d. COMMIT 4. A(n) _____-length character data type, like VARCHAR, is typically specified with a maximum length.