Dear Zoom Expert or frequent user 

I want to ask a technical question.

During a zoom meeting (educational classroom), Can zoom detect any participant is screen-recording with QuickTime player or other screen-recording app ( not the built-in record function in zoom)?

As a student myself, I asked, because during a meeting last week, the instructor speaker mentioned someone was privately screen-recording.
below only my photo instead of other student photo, a red REC was actively being displayed.
However, I did not press any record button on zoom app. Is there any probability that REC function can be turned on by speaker carelessly? I did not share my screen too.

Is the paid version zoom used by my instructor able to detect 3rd party screen-recording?
In the class, the instructor is delivering a boring 4-hr long presentation, reading textbook, and half of the class (11 out of 20) was not paying attention to his super-boring lecture. Some were eating dinner, some watching YouTube, radio listening, or doing assignment of other classes. I myself was browsing webpages and sometimes reading my physical book on desk only.

The instructor actively from time to time enlarged his screen to block my view of other concurrent browser page. Extremely forceful and impolite. He is aware his lecture contains zero insights and delivers a robotic interpretation of textbook content. 

I am using the latest free version 5.9.1 (3506) zoom on an old iMac, high sierra, 10.13.6.

For your help and reply please.

Regards

koh 
Zoom user (free version)

I am trying to have two meetings run concurrently.  Not the whole time, they may overlap by 15-30 minutes.  I have read THIS, but still don't understand how to start both meeting so that they won't cut off.  It says both have to be started by the host.  We are doing that.   Can you shed more light?