In determining the proper daily dosage for a new drug and the number of days of the medication period, it was found that the daily dosages formed an increasing arithmetic sequence and that the drug was most effective if the dosage on the 6th day was 31 mg and the difference in the dosage between the 6th day and the 10th day was 12 mg. The dosage (in mg) that is required on day 1 of the dosage period and the amount that the dosage is increasing by each day (in mg) are: Note: Let an represent the dosage on day n of the dosage period. Since {an} is an arithmetic sequence the am; = an + d, where dis the constant added each day, and 3,, = a1 + (n-1)d, where an is the general nth term. 0 a) 12,2 0 b) 12,3 0 c) 16,2 0 d) 16,3