ok, fine

了解(りょうかい)	OK, I get it! (originally used by the military, like “roger!”, it’s now used by young people who send short emails)

順調(じゅんちょう)	Going as expected, no problems. Satisfactory! Usually used like this:“Hi! How’s business these days?” “Oh, 順調、 I can’t complain!”

平気(へいき)	Young person’s word, particularly young females use this. OK, fine with me. Is it ok with you? 平気?