Choose the correct preposition(Избрать верный предлог)across, opposite,near, by, inext

Choose the correct preposition
(Избрать верный предлог)
across, opposite,near, by, inext to, on, between, among.
1. You'd better go...... foot if you're not tired.
2. He usually travels ....... train.
3. The post office is ..... the bank