Sql and Relational Algebra problem

The company wants to introduce a policy whereby an employee's salary should not be more than 10% the salary of their manager nor of directors of projects that they have submitted timecards for. Write a Relational Algebra expression and an SQL statement that determines if the data in a database satisfies this policy or not. This problem requires an explanation on how the result of the Relational Algebra expression and SQL statement can be used to answer this question. It should be clear from the result whether the policy is satisfied or not; that is, someone shouldn't have to go through the result one row at a time to find the answer.

Additional Info for database shown below salary stores the yearly salary of an employee zipcode attributes store strings date_submitted and start_date attributes store Date values "year" and "week" attributes store integers. Ex. one row may have values of 1995 and 19, which is the 19th week in the year 1995 DO NOT USE aggregate functions or subqueries. Be as simple and as beginner friendly as possible zipcodes zipcode City State 0.." FK PK employees CK1 id phone first_name last_name Street zipcode age salary manager PK CK 1 FK 0..1 10..1 0.1 1..1 10. timecards FK serial_number year week employee date_submitted PK CK 11..1 1.. FK timecard project hours_spent PK timecard_entries FK 1..1 PK code name CK budget start_date director FK 0.. projects