Catalogue is related to library books in the same way index is related to

Choose the correct alternative for the given relation.

Accomodation : Rent : : Journey : ?

Magnalium is to aluminium as brass is to........

Choose the correct alternative for the given relation.

Friendly : Inimical

Helm is related to rudder in the same way brain is related to........

Door is related to Bang in the same way as Chain is related to..........?