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]: ['6627', '8037', 'q', 'e', 'j', 'p', '9613', '9317', 'm', 'm', '5345', 'f', '8105', '5665', '4175', '4793', '3707', 'i', 'b', '6745', '747', '8329', '1481', 'b', '8949', 'n', '4803', '1359', '3533', 'f', '543', '3003', '6943']
[EX A]: b, e, f, i, j, m, n, p, q

[EX Q]: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']
[EX A]: m, o, r, u, v, y

[EX Q]: ['5195', '293', 'r', 'd', '6427']
[EX A]:
d, r