Which is the correct use of prepositions

[Kwong]

Could someone tell me which is the correct prepositiion used for the following sentences.

1a. I prefer to work at your office in Queen Street.
1b. I prefer to work at your office on Queen Street.
1c. I prefer to work at your office at Queen Street.

2a. The building is located in Queen Street.
2b. The building is located on Queen Street.
2c. The building is located at Queen Street.

3a. He is still in the school.
3b. He is still at the school.

Thanks in advance

[Mister Micawber]

These are OK:

1a. I prefer to work at your office in Queen Street.
1b. I prefer to work at your office on Queen Street.

2a. The building is located in Queen Street.
2b. The building is located on Queen Street.

3a. He is still in the school.
3b. He is still at the school.
_________________
Native English teacher at Mister Micawber's