Question

A group of 4 girls and 7 boys of a class go for a picnic. In how many ways they can stand in a row for a group photograph, if

1. All girls stand together 
2. All girls stand together and all boys stand together
3. Two tallest boys stand on the extremes
4. No two girls stand together
5. All the boys stand in the middle
6. If 2 boys and 1 girl are to be selected to represent the group for their future outings, how many ways can the team be selected?