Fill in either be used to or get used to in

Fill in either be used to or get used to in the appropriate forms.
1 For older people its rater difficult to change a place of living. Children get used to new environment much easier.
2
Are you feeling OK after the tour round the city? Would you like to take a car?
No, Im not tired at all. Im used to walking long distances, and enjoy it better than driving.
3 As a chemist, he was used to working with different substances and never got injured. However, he never let anyone into his lab when he was experimenting.
4
I cant start working from 7 am! Im not able to wake up so early!
Everyone says so. But youll get used to early rising in a week, and then, Im sure, youll enjoy it.