Question

5.Velocity of sound.........with an increase in the temperature of the medium.
a.decrease
b.increases
c.remains the same
d.none of these

Answer 1

b)Increase
Molecules at higher temperatures have more energy, thus they can vibrate faster. Since the molecules vibrate faster, sound waves can travel more quickly. 

Answer 2

b. increases as with the speed in temperature the vibrations of particle increase.so it's velocity increases.