Write each in exponential notation

1. 7•7•7•7 =
2. 2•2•2•n•n•n =
3. 10•10•b•b•b•b =
4. (a-1) (a-1) (a-1) (a-1) (a-1)
5. {(a-1)-2b {(a-1)-2b {(a-1)-2b)