If ~$a, b, k$~, and ~$m$~ are positive integers, is ~$a^k $~a factor of ~$b^m$~?
(1) ~$a$~ is a factor of ~$b$~.
(2) ~$k ≤ m$~
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
(1)a是b的factor,表达为ay=b。