Presenting a meeting from Rome, Italy via 4G wifi hotspot. How much data will a 75 minute meeting consume?

It does depend on what you are doing, but I would suspect that you could go over.

Things like live video can range from 100 kbps to 500 kpbs. Screen sharing can consume that much or more, depending on the resolution of your monitor. Audio runs about 44 kbps. Content bandwidth demand is dictated by that content's settings. MP4 or FLV video can be set to stream at 10+ mbps, though I try to stick with 800 kpbs. In short, there is no hard line answer of it will or won't work. You just need to do some math to figure it out.

For example:

Duration 75 min

Audio (44 kbps):                                                                       198 mb

Live Video (400 kbps):                                                              1800 mb

Screen Sharing (1024 X 768 resolution 150 kbps):                 675 mb

It would be easy to go over your data limit, so just prioritize your needs for the meeting and use only what you need. If you need live video, do it for the opening and closing, but then stop doing it during the presentation, as it only takes up bandwidth and draws focus away from your presentation.You can also reduce the room bandwidth to DSL (limits the room to 600 kbps max) or Modem (limits room to 56 kbps) to help conserve on bandwidth. However, you will notice a reduction of quality to compensate for the bandwidth restrictions. To help with some of the math, here is a Technical Overview of Connect 9, http://www.realeyes.com/wp-content/uploads/2014/06/Adobe-Connect-9-Technical-Guide.pdf. On the next to last page, there is some numbers for you to work with.