Two cars approaching each other, The first car is a police car that moves at 72 km/h while the second car moves at 90 km/h, The police car started its siren with a frequency of 650 Hz. If the speed of the sound is 350 m/s, then what is the frequency of the sound heard by the driver of the second car from the police car?

He sandals were out in the sun so the got hotter. which is why her feet felt hot.

Idk just need points

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.