A:AnswerNo, only if you have a smart card/sim/sd card reader because there is a usb connection (rectangular port) slot to connect to with any usb device.
A:AnswerYes, works with MACs and iPad Pros, but New iPad Pros that came out November 2018 which are iPad Pro 11” and iPad Pro 12.5” with USB-C charging port.
A:AnswerIf it's within the return period (usually 14 days I believe) then yes, you can. Most items work that way unless its a special case. In the future, it's a good idea to check compatibility before purchasing... if you can tell it won't work with it still in the box, you could also tell before buying.
A:AnswerVideo adapters that work with iPads (this one only works with the 2018 iPad Pros and we can assume future devices as well, since it is USB-C and not Lightning) can mirror mostly anything that comes up on the iPad display while connected to an external display. Some apps do not allow this or have a separate display for the external device, but for the most part everything will be mirrored.
A:AnswerNo - this only works on the latest Macbook Pros with USB-C ports. It will not work with an older Macbook or your iPad as they do not have the ports needed to support this dongle.