Question: How many of those 3 are currently teaching courses?
SQL: SELECT count ( DISTINCT t3.emp_num )  FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num   =   T2.emp_num JOIN professor AS T3 ON T2.emp_num   =   T3.emp_num JOIN department AS T4 ON T4.dept_code   =   T3.dept_code WHERE T3.dept_code   =   'ACCT'