A:
I know you can watch downloaded content from a micro SD card up to 64gb. Just insert the micro SD card into the slot allow it time to process your card then go to folder or the video app icon and view whatever is on the SD card. You can also load directly to the memory of the tablet though I don't recommend that depending of the internal size of you drive such as 8gb, 16gb, 32gb...
As for an actually FLASH DRIVE there's no plug-in directly into the tab for that to work.