Under what condition the average speed of a body be equal to its average velocity?

Sounds propagates through some kind of medium. usually it's air, but it goes just as well through solid objects like walls, windows etc. a soundwave will compress the (air)molecules in front of it, and if this increased density wave hits your ears, you register it as sound. solid objects like walls are a lot denser than air, this means that they will damp a wave, but also carry it easier.

Im not from america so could you explain what route 70 is? how much km or miles does it have? am i supposed to know ,from this text,what the s(road) is? how many km or miles it has?

Iwas thinking the wavelength is one half its original value