Coucou j'ai du mal pourriez vous m'aidez? Et merci a ceux qui m'aideront

Bonjour, voici tes réponses :
1. Bill Gates is one of the richest men in the States.
2. The London Rits is the most comfortable hotel in the world.
3. Céline Dion is one of the most popular Canadian singer.
4. Jim is the happiest Yellowknife.
5. The Rolls Royce is one if the most expensive car.
6. Siberia is the coldest place in the world.
7. Toronto is one of the safest town in the world.