Waves Part 2

In a closed organ pipe, the frequency of fundamental note is 30‌Hz. A certain amount of water is now poured in the organ pipe so that the fundamental frequency is increased to 110‌Hz. If the organ pipe has a cross-sectional area of 2cm2, the amount of water poured in the organ tube is _______g. (Take speed of sound in air is 330m∕ s )