Fred, Barney and Ralph belong to the La Trobe Mountain Club. Every member of the Club is either a skier or a hiker. Anyone that doesn't like snow does not like skiing. No hikers like rain. Ralph dislikes whatever Fred likes, and likes whatever Fred dislikes. Fred likes rain and snow.  

(a)  Choose a suitable set of predicates, functions and constant symbols for representing the above knowledge in First Order Logic, and provide a glossary where you indicate their intended meaning.

(b)  Using only the predicates, functions and constant symbols you have described above, write sentences in first-order logic that represent this knowledge. 

(c)  Convert the sentences into clausal form and give the resulting set of clauses. 

(d)  Use resolution refutation to find the member of the Mountain Club who is a hiker but not a skier. Show the complete resolution derivation (in sequence or tree form), clearly indicating which clauses are resolved, and the unifier used.