My subjects say we need 2 hours study for every hour lecture. I generally get through what i need to in an hour. I also read a lot of other stuff and waste time on BL, but I have still been getting through it all and remembering it.
I use a mixture of piracetam, picamilon, ephedrine, caffeine, lions mane mushroom caps, huperzine-a. Sometimes I replace piracetam with noopept.
I can do multiple things at once. I can listen to music and get through engineering equations. i can design things. Sometimes i don't even need a calculator. My stack is the bomb.