668 Ἆρα and ἦ mark a sentence as interrogative, implying nothing as to the answer expccted.

For μή and μῶν in questions see 488 a, c. οὐ in a question is like English not, implying that the answer yes is expected; so also οὐκοῦν, but less strongly. ἆρα before μή or οὐ merely makes the interrogative force more distinct.

Πότερον (πότερα) . . . ἤ introduce the members of an alternative question, utrum . . . an. ( Whether . . . or was formerly used in the same sense, but whether is not so used in modern prose in a direct question.)