I485 application materials

My I140 (EB1) is approved recently. Therefore, I plan to submit I485 for myself, my wife and son. I have a couple of questions about the documents required. It is highly appreciated if you could give advices.

(1) Documents for myself should include: I485, G-325A, letter of employment, birth certificate, what else?
(2) Documents for my wife and son should: I485, G-325A, I864, birth certificate, what else?
(3) Should all three application put in one envelop or in a separate one?
(4) Should we have medical examination before submission?