In the front / In the back / At the front / At the back / On the front / On the back?

1. I don't like to sit ___ the front of the cinema when I see a movie.

2. Normally the garden is ___ the back of the house.

3. I wrote the telephone number ___ the back of the cheque.

4. We normally use the front entrance to the building, but there's another one ___ the back.

5. I prefer to sit ___ the front of the car.

6. We were ___ the back, so we couldn't see very well.