kako ste

1. how are you?
   Dobar dan, gospođo Jovanović, kako ste? — Good afternoon, Mrs Jovanović, how are you?
   Deco, kako ste? Jeste li se lepo proveli? — Kids, how are you? Did you have a good time?

Used formally to one person or to several people; the usual answer is "Dobro, hvala, a vi?".