hi adi,
I would say that you have learnt the basics of resistive dividers and OPA's, of course its a never ending process, as more technology is developed.
I think i am done with it. I tried my best to do it myself. I don't have any friend here as i moved from down south here. Plus Covid19 make it almost impossible. Sorry guy for wasting your time.
Eric Seriously i did my best. In 4 lecture i will never become expert. I spent 4 days non stop to do the best i could. I can't learn electronic and simulation in such a short time. It does look me very stupid honestly.