la vitesse de l'hélicoptère par rapport à la masse d'air en dehors de la veine en mouvement (vitesse dite infini amont ; on notera que si v v = 0 displaystyle v_ v =0 Immediately after alot of trial and fails, with alot of different methods, which include glass bulb vaporizer, two litre bottle with tinfoil, h2o bong, And eventually electronic m