As I wrote the post I did't know the size of the audience but if there was going to be anyone at the back that couldn't see my slides :-) ... they could go online to see this key slide about my RATES Marketing Strategy.
The reason I'm showing this is to demonstrate how it's possible to use "no cost" technology to allow anyone, anywhere to see slides, or anything else, in real time. This particular slide went live after I started my morning presentation. If I had wished I could have made each slide visible as I proceed through the presentation.
The method used is to write the post and set it up to auto-publish when you want it to go live. And if you want an extra flourish you can set it up to also post to social media at the same time.