Between the faculty employee professors, how many teaches high-level or harder undergraduate courses? Indicate each of the professors unique identifying number.
faculty employee professors refers to hasPosition = 'Faculty_eme' and professor = 1; high-level or harder undergraduate courses refers to courseLevel = 'Level_400'; professors unique identifying number refers to person.p_id
SELECT COUNT(*) FROM person AS T1 INNER JOIN taughtBy AS T2 ON T1.p_id = T2.p_id INNER JOIN course AS T3 ON T3.course_id = T2.course_id WHERE T1.hasPosition = 'Faculty_eme' AND T1.professor = 1 AND T3.courseLevel = 'Level_400'