Boojho took an empty plastic bottle, turned it upside down and dipped its open mouth into a bucket filled with water. He then tilted the bottle slightly and made the following observations.

(i) Bubbles of air came out from the bottle.

(ii) Some water entered the bottle.

(iii) Nitrogen gas came out in the form of bubbles and oxygen got dissolved in water.

(iv) No bubbles formed, only water entered the bottle. Which observations is/are correct?