yes.
-A#是不是就是485 receipt上的Alien號碼?
yes.
-Part 1 - 3 Class of Admmission 是啥?
your current status. for example, if your current status is H1B1, then the class of admission should be H1B1
-如果Expected length of trip填一個月,會不會就給個一個月的證件?
i do not think so. usually, they will issue AP valid for one year.
-怎麽陳述理由呀,我好像沒什麽Emergent situation
they do not really care about the reason why you have to travel. visiting elderly is good enough.
寄到什麽地方呢?我現在是485pending,那是寄到Service center 呢還是District office?
should be service center
一家三口是填三分表麽?能不能寫一張總的Check放在一個信封寄過去
i think you'd better fill three forms and write separate checks.