Which of the following is correct? If a firm sells on 2/10 net 30 and its DSO it 30 days then all its customers pay on the 30th day If a firm sells on 2/10 net 30 and its DSO is 40 days then none of its customers are taking advantage of the discount If a firm sells on 2/10 net 30 and it changes it's credit terms to 3/10 net 30, its DSO should decrease If a firm sells on 2/10 net 30 and its DSO is 9 days then all its customers are taking advantage of the discount