display the employee number and name( first name and last name ) for all employees who work in a department with any employee whose name contains a ’T’.
SELECT employee_id ,  first_name ,  last_name FROM employees WHERE department_id IN ( SELECT department_id FROM employees WHERE first_name LIKE '%T%' )
employees who work in a department with any employee whose name contains a 'T' refers to a subquery filtering employees with 'T' in their first name; display employee number and name refers to selecting employee_id, first_name, and last_name;