internal table에 대한 O,X 문제?

1. data object that allow user to retain several data records with the Different structure in memory

2. internal table's attributes are line-type, key definition,database?

3. internal tables can sort data from database table for process?

4. internal tables structure and format is for input?

5. table's format data for use by other service?

ABAP 공부를 하고 있는데 위의 문제의 답을 모르겠어요..ㅜㅜ

좀 알려주세요~~ ^^;