What time do you go to bed? What time do you usually get up? How much time do you have for sleeping?
I heard that some people (like Elon Musk) sleep for 4 hours in order to have more time to do things during the day. Is it dangerous to health?
I used to go late to bed but I recently started a new job that I have to start working on 5am.
Having said that, I usually go to bed around 10 pm. this is around 6-7 hours sleep for me - personally I think that 4 hours is so less, even 7 hours is not enough but it depends on the person.