Every time you enter a car there is a higher chance of “will I die during this trip” than when you enter a plane.
Yes the “chance to survive a plane crash” is lower than the “chance to survive a car crash” but the chance to ever be in a plane crash is incredibly low, even when you factor in the number of cars vs number of planes etc.
That’s wrong. The tube has a cross section of 0.25π cm² so your tube will be filled ~1,2732m high.
Also as others have stated, if you can measure 1cm you already have a definition of a Meter.