$A$ closed organ pipe and an open organ pipe have their first overtones identical in frequency. Their lengths are in the ratio

In a resonance column lab experiment to measure the velocity of sound,the first resonance is obtained at a length $l_1$ and the second resonance at a length $l_2$. Then-

An open pipe of length $L_1$ has a fundamental frequency $n_1$,and a closed pipe of length $L_2$ has a fundamental frequency $n_2$. If they are joined to form a single closed pipe of length $L = L_1 + L_2$,what is the fundamental frequency of the combined pipe?

If in an experiment for determination of velocity of sound by resonance tube method using a tuning fork of $512 \ Hz$,the first resonance was observed at $30.7 \ cm$ and the second was obtained at $63.2 \ cm$,then the maximum possible error in the velocity of sound is ..... $cm/s$ (consider the actual speed of sound in air is $332 \ m/s$).

$A$ uniform tube of length $60.5\,cm$ is held vertically with its lower end dipped in water. $A$ sound source of frequency $500\,Hz$ sends sound waves into the tube. When the length of tube above water is $16\,cm$ and again when it is $50\,cm,$ the tube resonates with the source of sound. Two lowest frequencies (in $Hz$),to which the tube will resonate when it is taken out of water,are (approximately).

$A$ student is performing an experiment using a resonance column and a tuning fork of frequency $244 \ s^{-1}$. He is told that the air in the tube has been replaced by another gas (assume that the column remains filled with the gas). If the minimum height at which resonance occurs is $(0.350 \pm 0.005) \ m$,the gas in the tube is. (Useful information: $\sqrt{167 RT} = 640 \ J^{1/2} \ mol^{-1/2}$; $\sqrt{140 RT} = 590 \ J^{1/2} \ mol^{-1/2}$. The molar masses $M$ in grams are given in the options. Take the value of $\sqrt{\frac{10}{M}}$ for each gas as given there.)