Based on the tables below, which of the following SQL commands would return the average customer balance grouped by SalesRepNo? GENERAL SALES DATABASE: SALESREP CUSTOMER SELECT AVG (Balance) FROM CUSTOMER GROUP BY SalesRepNo; SELECT AVG (Balance) FROM CUSTOMER, SALESREP WHERE SALESREP.SalesRepNo - CUSTOMER.SalesRepNo; SELECT AVG (Balance) FROM CUSTOMER WHERE SalesRepNo; SELECT Balance FROM CUSTOMERAS C ORDER BY C.SalesRepNo