dimagi paheli - 121 Why bats sleep upside down ? Riddles for IQ Test| Hindi Paheli #Shorts

Paheli kept some water in a beaker for heating. She observed that tiny bubbles appeared before the water started to boil. She boiled the water for about 5 minutes and filled it in a bottle up to the brim and kept the bottle air tight till it cooled down to room temperature (a) Why did the tiny bubbles appeared ? (b) Do you think tiny bubbles will appear on heating the water taken out from the bottle? Justify your answer.