If the temperature of the atmosphere is increased,which of the following characteristics of a sound wave is affected?

The temperature at which the speed of sound in air becomes double of its value at $27^\circ C$ is ... $^\circ C$

The ratio of the velocity of sound in hydrogen gas $(\gamma = 7/5)$ to that in helium gas $(\gamma = 5/3)$ at the same temperature is

$A$ source of frequency $f$ is emitting sound waves. If the temperature of the medium increases,then

$A$ tuning fork of frequency $220 \,Hz$ produces sound waves of wavelength $1.5 \,m$ in air at $N.T.P$. The increase in wavelength when the temperature of air is $27^{\circ} C$ is nearly $\left(\sqrt{\frac{300}{273}}=1.05\right)$ (in $\,m$)

The ratio of the speed of sound in helium gas to that in nitrogen gas at $295 \text{ K}$ is (Ratio of specific heats for helium is $5/3$ and that for nitrogen is $7/5$. Molecular weight for helium and nitrogen are $4$ and $28$ respectively.)