The active voice or the pfssive voice? Use the appropriate forms

The active voice or the pfssive voice? Use the appropriate forms or the verbs and write down the sentences. 1) a)Cristopher Columbus (discover) America in 1492. b) Nobody knows when this fact ( discover). 2) a) The Post Office Tower in London (build) in 1964. b) It (build) to make the telephone and television systems of the British capital better. c) Who (build) the Tretyakov Gallery in Moscow? 3) a) The small island (not.show) on the map. b) Mrs Pitkin (not.show) me her garden when I came to visit her. 4) a) Mr Woodriff (paint) very good portraits when he was younger. b) A lot of strange animals (paint) on the wall. We couldnt see all of them. 5) a) Jonathan Swift (write) quot;Gullivers Travelsquot; in the 18th century. b) quot;Battle of the Booksquot; (write) by him too.