Read the following statements w.r.t regulation of respiration.

(i) Neural signal from pneumotaxic centre (pons) can reduce the duration of inspiration and thereby alter the respiratory rate

(ii) The role of oxygen in the regulation of respiratory rhythm is highly significant

(iii) A chemo-sensitive area situated to the rhythm centre (medulla) is highly sensitive to CO₂ and hydrogen ions

(iv) Receptors associated with aortic arch and carotid artery can recognise changes in CO₂ and H⁺ concentration

(v) Medulla of brain has insignificant role in the respiratory regulation.

Which of the above statements are correct ?