An open pipe of length $33 \, cm$ resonates to a frequency of $1000 \, Hz$. The mode of vibration is: (velocity of sound $= 330 \, m/s$)

This question has Statement $1$ and Statement $2.$ Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement $1:$ In the resonance tube experiment,if the tuning fork is replaced by another identical tuning fork but with its arms filed,the length of the air column should be increased to obtain resonance again.
Statement $2:$ On filing the arms,the frequency of a tuning fork increases.

$A$ man can hear sounds in the frequency range $120 \, Hz$ to $12020 \, Hz$ only. He is vibrating a piano string having a tension of $240 \, N$ and a mass of $3 \, g$. The string has a length of $8 \, m$. How many different frequencies can he hear?

An air column in a pipe,which is closed at one end,will be in resonance with a vibrating body of frequency $166 \,Hz$,if the length of the air column is .... $m$. (Assume the speed of sound in air is $332 \,m/s$)

In an open-end organ pipe of length $L$,if the velocity of sound is $V$,then the fundamental frequency will be (Neglect end correction).

Two open organ pipes of fundamental frequencies $n_1$ and $n_2$ are joined in series. The fundamental frequency of the new pipe so obtained will be