Problem 1 18 pts (3 points each): Six Sequences For each of the sequences below, state whether it is arithmetic, uadratic, geometric, or neither. If the sequence is of one of the three types, then give a closed formula for its general term. Assume that indexing starts at 1. For example, the sequence a= (9, 13, 16, 20, 24, 28, ) is arithmetic with difference 4. Its general term is given by the formula an-54n (for n 2 1) i. 6,18,54, 162, 486, 1458,.. ii. 20, 17,14,11, 8,5,... iii. 12,-24, 48,-96, 192,-384,.. iv. 5, -9, 13,-17,21,-25,... v. 4,12, 26, 46, 72, 104, vi. 520 x 76, 519 x 77, 518 78, 517 79, 516 x 710, 515 x 711