Which preposition is the correct one?

Wai - man works ____ the best Chinese restaurant in town.
1. as
2. at
3. in
4. on
5. with
I think working _____ other people is more fun than working alone.
1. as
2. at
3. in
4. on
5. with
I hate working ______ the media. It would be nerve - racking!
1. as
2. at
3. in
4. on
5. with
Working ____ a dance instructor sounds great.
1. as
2. at
3. in
4. on
5. with
Working ____ an office is less interesting that working ____ a cruise ship
1. at, in
2. in, at
3. with, with
4. in, on