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So it is possible to ask ''how are you?'' so..Apa kabar kamu? or no,only Apa kabar Anda?

apa kabar kamu - this is a non-formal way to say how are you

apa kabar anda - this is a formal way to say how are you

so it's ok to use both :)

Use 'kamu' for people you already know - better yet, wait until they use kamu (or kau) and follow the example.

Litterally, it means "what news (with) you?" or "what (is) your news" (more correctly said as, "Apa kabar mu?")

prefer to say " Apa kabar?"