In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

Q: ['4749', '4607', '625', '6907', 't', 'b', '8479', '6505', 'r']

A: b, r, t
****
Q: ['g', '6867', '7965', '3313', 'k', '1827', '7337', 'u', '1209', '5145', 'w', 'h', '9059', 'u', 'b', '3189', '2837', 'k', 'y', 'e', 'b', '4479', '541', '7103', 'h', 'm', '2177', '6377', '3993', '7167', 'q', '2145', '5007', '9135', '5331', 'e']

A: b, e, g, h, k, m, q, u, w, y
****
Q: ['235', 'j', 'q', 'b', 'r', 'w', 'g', '5227', 'n', '5223', 'e', '9261', '6701', '4635', '245', 'a', '2563', '7275', '8439', 'h', 'q', '4371', '6553', '5295', '2477', 'i', 'n', 'x', 'f', '6353', '975', '2047', '4085', 'm', '303', 'q', '5011', '1619']

A:
a, b, e, f, g, h, i, j, m, n, q, r, w, x
****