Give me the code that fits the question. Please give me the code that fits the question. It's really important. And please use the table shown in the screen shot that I uploaded.

Question

Update the salaries of the instructors as follows.

Increase salary by 6% for the instructors who taught at least 3 different courses (different course_id);

Increase salary by 4% for the instructors who taught exactly 2 different courses;

Increase salary by 2% for other instructors (including the instructors who did not teach).

Please use BEGIN TRAN and ROLLBACK properly (CREATE VIEW is not allowed to use; you may use the WITH clause within BEGIN TRAN and ROLLBACK). You must use the CASE expression.