Which of the following statements is wrong?

The speed of sound in oxygen $(O_2)$ at a certain temperature is $460 \,ms^{-1}$. The speed of sound in helium $(He)$ at the same temperature will be (assume both gases to be ideal): (in $\,ms^{-1}$)

At constant pressure,out of $H_2$ and $O_2$ gas,in which gas is the speed of sound greater?

Explain the propagation of sound waves in:
$(i)$ air
$(ii)$ solids

$A$ train,standing in a station yard,blows a whistle of frequency $400 \, Hz$ in still air. The wind starts blowing in the direction from the yard to the station with a speed of $10 \, m/s$. Given that the speed of sound in still air is $340 \, m/s$. Mark the $INCORRECT$ statement:

The speed of sound in air is independent of its: