Problem 4. (2 point) Consider the following Knowledge base (KB) as follows: u. Tenured (u) v. Tenured (v)Fat(v) w.Fat(Boss(w))Fat(w) Boss(Andrew) = Bob Tenured(Bob) (1) Is "Fat" a predicate symbol, a function symbol, or a constant symbol? Explain by steps in details. (2) Is "Boss" a predicate symbol, a function symbol, or a constant symbol? Explain by steps in details