When I need to reduce the person I'm meeting with in order to have a document on my screen, the thumbnail is extremely small.  In Skype and other meeting platforms, I'm able to use the mouse to resize the image.  Zoom doesn't seem to be able to do this.  There must be some way to enlarge the thumbnail.  The person I'm talking to is barely visible in the default size.   When I Google this problem, the result I get is to hit 2X, but that solution does not work. 

Whenever I host a meeting the audio doesn't work for anybody. I can't hear them and they can't hear me.

All my audio settings are normal. The weird part is when i join someone else's meeting the audio is all good.

Not sure what to do, If you know what's up please help. 
Thank you.

Most of my days I am booked in back to back meetings on the half hour. If a meeting is running over, my next meetings participants are able to join. How do I disable that? I've enabled the waiting room setting, but that is not doing the trick. I want to be able to stop the next meeting attendees from joining a call that is running over. 

In a recent 2-person Zoom call, the host was unable to unmute himself.  He found his mute icon and made sure he wasn't muted, but I still couldn't hear him.  I can speculate that his microphone was simply broken or disconnected from his computer, but this was a regularly practicing lawyer, so that seems unlikely. I'm wondering if there is an alternate explanation.

If there is, I need to know, because I'm new to Zoom, and about to host a large family meeting. It would be embarrassing if nobody could hear me.