1. The first row of seating in an outdoor amphitheater contains 26 seats, the second row contains 29 seats, the third row contains 32 seats, and so on. (a) Explain why the number of seats in each row can is an arithmetic sequence. because the common difference is d = 3 (b) Determine the general term of the sequence, an an = a + (n-1) d an = 26+ (n-1) 3 (c) Suppose there are 20 rows. Write the partial sum using the sigma notation for the total number of seats. (d) What is the total seating capacity of the theater?