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.

[EX Q]: ['n', 'g', 'u', '2873', 'k', '4411', 'w', '8179', 'w', 'w', 'f', 'g', 'e', '7837', '3055', 'z', 's', '6037', 'n', '1479', 'c', '5311', 'i', 'w', 'z', '1891', '9663', 'y', 'f', 'h']
[EX A]: c, e, f, g, h, i, k, n, s, u, w, y, z

[EX Q]: ['8495', 'p', 'j', 'm', 'n', '9115', '1183', 'r', 'r', '8735', 'a', 'i', 'k', 'p', '8927', 'r', '9283', '9563', 'g', '2503', 'h', '1091', '5257', 'a', '3061', '2835', 'l', 'w', 'j', '7617', '8793', '7463', 'h', '8467', '7337', 'b', '4655', 'd']
[EX A]: a, b, d, g, h, i, j, k, l, m, n, p, r, w

[EX Q]: ['5763', 'l', '9749', '2151', 't', 'b']
[EX A]:
b, l, t