anywhere between 2 to 3 minutes, depends upon speed at you are walking.
Type O, since it contains no antigens
Type O, negative, to be more speciifc (with negative referring to the Rh factor)
Is widely considered the universal blood type. It is very important because it potentially be transfused to any patient regardless of their blood type. Especially in emergency situations, when there isn't enough time to determine a patients blood type.
It's something on the internet that is like a fad. For instance the rick roll thing.