Two adjacent angles whose sum is 180∘ is called
Fill in the blanks so as to make the following statements true: (i) If one angle of a linear pair is acute, then its other angle will be___. (ii) A ray stands on a line, then the sum of the two adjacent angles so formed is ___. (iii) If the sum of two adjacent angles is 180∘, then the ___ arms of the two angles are opposite rays.