航空货运单的作用，除了是承运人与托运人之间缔结的运输契约和承运人收运货物证明文件之外，还是()。
（）isadocumentgrantedbythecustomsauthoritieswhichallowsavesseltostartunloadinggoods.
Simplifiedwordsarecommonlyusedintelexmessagesbecausethechargeforatelexisbasedon（）.
Underthevechartering，theshipownerisresponsibleforthefixedrunningexpensesaswellasfortheveexpenses.