In a pipe closed at one end, an air column is vibrating in the fourth overtone. If the vibrating air column has $x$ nodes and $y$ antinodes, then the values of $x$ and $y$ are respectively:

$A$ closed pipe of length $300 \,cm$ contains some sand. $A$ speaker is connected at one of its ends. The frequency of the speaker at which the sand will arrange itself in $20$ equidistant piles is close to .......... $kHz$ (velocity of sound is $300 \,m/s$).

$A$ source of frequency $340 \,Hz$ is kept above a vertical cylindrical tube closed at the lower end. The length of the tube is $120 \,cm$. Water is slowly poured in just enough to produce resonance. Then, the minimum height (velocity of sound $= 340 \,m/s$) of the water level in the tube for that resonance is (in $\,m$)

$A$ resonance air column of length $20 \ cm$ resonates with a tuning fork of frequency $250 \ Hz$. The speed of sound in air is .... $m/s$.

$A$ pipe $30 \ cm$ long is open at both ends. Which harmonic mode of the pipe is resonantly excited by a $1.1 \ kHz$ source? (Take speed of sound in air = $330 \ ms^{-1}$)

In a resonance tube,the first resonance is obtained when the level of water in the tube is at $16\,cm$ from the open end. Neglecting end correction,the next resonance will be obtained when the level of water from the open end is .... $cm$