The intensity of sound increases at night due to

$Assertion :$ Sound travels faster in solids than gases.
$Reason :$ Solids possess greater density than gases.

$A$ $SONAR$ (sound navigation and ranging) uses ultrasonic waves to detect and locate objects under water. In a submarine equipped with a $SONAR$,the time delay between generation of a probe wave and the reception of its echo after reflection from an enemy submarine is found to be $77.0\; s$. What is the distance of the enemy submarine (in $; km$)? (Speed of sound in water $= 1450\; m/s$)

Which of the following statements are wrong about the velocity of sound in air?

$A$ man,standing between two cliffs,claps his hands and starts hearing a series of echoes at intervals of one second. If the speed of sound in air is $340 \, ms^{-1}$,the distance between the cliffs is .... $m$

On a windless day,sound emanates isotropically from a point source. Rays of the sound waves emanated from a point source placed close to the ground are shown in the figure. Consider horizontal wind towards the left blowing with constant velocity,which is uniform everywhere. In the following figures,rays of sound waves in the presence of the wind are shown. Which one is the most correct representation?