<prompt> Which of the following muscle relaxant has the maximum duration of actionAtracuriumVecuroniumRocuronimumDoxacurium  <response>: Non-depolarising blockers : long acting 50min: d-tubocurare , pancuronium, doxacurium, pipecuronium Intermediate acting20-50mins : Vecuronium, Atracurium, cisatracurium, rocuronium. Sho acting20mins : Mivacurium, Rapacuronium. 