1. If 8, a, B, C, 26 are known to form an arithmetic sequence, find the average and sum of these five numbers, 1. It is known that 8, a, B, C and 26 constitute the arithmetic sequence, and the average and sum of these five numbers are obtained 2. It is known that 8, a, B, C, D and 26 constitute the arithmetic sequence, and the average and sum of these six numbers are obtained
seventeen