Put in the correct prepositions AT / ON / IN:
1. Columbos discovered America 1492.
2. You can see the stars ............... night, if the sky is clear.
3. Tom isn't here ............. the moment. He'll be back ............. five minutes.
4. The course begins ........... 7 January and ends ............ 10 March.
5. Tom's grandmother died ........... 1977 ........... the age of 79.