Table: Employee | Column Name| Type| | id | int | | int | | salary +- -------+ id is the primary key column for this table. Each row of this table contains information about the salary of an employee. Write an SQL query to report the second highest salary from the Employee table. If there is no second highest salary, the query should report null.

Employee (Lastname, FirstName, MidInitial, gender, street, city) Works (Lastname, FirstName, MidInitial, company-name, salary) Company (company-name, city) Write an RA query (Not SQL command) Find the names of companies which have employees living in Lincoln and Omaha. (If a company only has employees live in one of these two cities, not both, then it should not be included in the result.)

Using the university schema, write an SQL query to find section(s) with maximum enrollment. The result columns should appear in the order “courseid, secid, year, semester, num”. (It may be convenient to use the with construct.)