Like everyone said memorize the textbook and remember his weirdass stories . I also found this test completely different from last time . <| sep |> I think you have to hold your breath for quite a bit longer to actually cut off oxygen from your brain . I mostly just hold it in for about 3 seconds , inhale a bit more before exhaling . But like I said , I see a lot of people who seem to exhale immediately and it just seems to me that it couldn ' t be absorbed that fast , but what do I know I ' m not a scientist . <| sep |> Some I know nothing about yet can imagine it is hazardous ! <| sep |> I agree . That ' s why I think some more testing than just 1 , 8 m log needs to be done . <| sep |> The main difference is the contrast ratio . The LG has a native contrast ratio and the Vizio has a dynamic contrast ratio . r a t i o o r h o w e v e rytvmanufacturerliestoyou As you can see , a display with a high native contrast is the way to go , if that ' s what you ' re going for . The night sky is black , but the streetlights pop out . The day sky is bright , but the dark jacket is dark . This is more like CRT , more like film , more like life . Also , the LG has a higher refresh rate 120 Hz over Vizio ' s 60 Hz . IMO , even though the LG is a 2015 model , it looks a lot better than the 2016 Vizio .