You will generally get much better responses from other users with fewer questions per post.
Some of these have inferred answers you can find with the search function and a moment to read through posts.
For example:
there is talk about visible here: Faster speeds with verizon + att or verizon + verizon or att + att cellular connections? - #4 by mystery
Yes it is.
They are all 850Mhz I think the notation is a reference to intraband carrier aggregation - I bet @sitloongs will be able to tell us if that’s the case 
Looks like you need questions answered about Google Fi particularily - lets edit the subject to reflect that and see if that draws in some expert answers…