(a) Write the following sentences using the predicates mb(x) = x is a metal building; tall(x) = x is a tall building; tower(x) = x is a tower; bridge(x) = x is a bridge;

inFrance(x) = x is in France.

Use Eiffel as a constant, it is the name of a famous tower in Paris.

1. Some metal buildings are tall.

2. Every metal building is a bridge or a tower.

3. The Eiffel tower is not a bridge.

4. France has many tall buildings.

5. Tall buildings are made of metal.

6. The Eiffel tower is tall.

7. There are no tall metal buildings outside of France.

(b). Convert the knowledge base to CNF.

(c). Prove using resolution with refutation that The Eiffel tower is a metal building and is in France.

Show the steps in the proof.