Write a query which will retrieve the values of salesman id of all salesmen getting orders from the customers in orders table without any repeats. Sample table: orders ord_no 70001 70009 70002 70004 70007 70005 70008 purch_amt ord_date customer_id salesman__ 2012-10-05 3005 2012-09-10 3001 2012-10-05 3002 2012-08-17 3009 2012-09-10 3005 2012-07-27 3007 2012-09-10 3002 150.5 270.65 65.26 110.5 948.5 2400.6 5760 5002 5005 5001 5003 5002 5001 5001