For each of the following sequences: [3 pts.] identify if the sequence is arithmetic, geometric or quadratic . Justify your response. [6 pts.] Assuming the first term of each sequence is a1, give an expression for ai. (In other words, find a formula for the i-th term in the sequence). [14 pts.] if the sequence is arithmetic or geometric, compute the sum of the first 15 terms in the sequence. Show your work. If the sequence is quadratic, then show.