(N/A) $(i)$ Sound requires a material medium for propagation and cannot travel through a vacuum. Since the moon has no atmosphere (vacuum),sound waves from an explosion cannot travel to a nearby point.
$(ii)$ The speed of sound depends on the medium's elasticity and density; it is generally highest in solids,followed by liquids,and lowest in gases. Additionally,the speed of sound increases with an increase in temperature because the kinetic energy of the particles increases,facilitating faster transmission of vibrations.
$(iii)$ The loudness of sound depends on two main factors: $(1)$ Amplitude of the sound wave and $(2)$ Sensitivity of the listener's ear.