'Call' in the Bible

As he saith also in Hosea, I will call that my people, which was not my people; And her beloved, that was not beloved.

For there is no distinction between Jew and Greek: for the same Lord is Lord of all, and is rich unto all that call upon him:

for, Whosoever shall call upon the name of the Lord shall be saved.

How then shall they call on him in whom they have not believed? and how shall they believe in him whom they have not heard? and how shall they hear without a preacher?