at higher altitudes the density of the air decreases. sound waves don't travel very well through less dense objects, for example, in space there is no sound at all.
An echo is heard due to the reflection from a rigid obstacle.
Volume
Light makes no sound, hence there is no "sound of light", and anything that doesn't exist cannot be heard.
A sound that can be heard in ordinary human ear is audible sound. It is approximately between 20 to 2000 decibel in strength.sound which is audible.. I.e. sound you can hear, as opposed to sound beyond human hearing at very low or very high frequencies.sound that is capable of being heard; sound loud enough to be heard; sound that is actually heard.
Audible
Cellular phones rely on signal towers erected all across the country of the mobile service. Technological science makes continued efforts every day to improve this signal in hard to reach places everywhere. Cellular phones often have bad signal due to poor location or a poor signal receptor. Mountainous areas as well as less populated areas are often the grounds of a signal lost or a signal that cannot be heard through.
India
malcome
trashbird
Exclamation points
Some restaurants do allow dogs in the dining area. This is becoming more common, especially in restaurants with outside eating areas.
radio transmission can be heard in hilly areas because of diffraction
Exclamation points
"Mate" is frequently used, "pal" not so much. "Excuse me, mate", or "Thanks, pal." Different areas of the UK will often use local words. In Newcastle Upon Tyne "Marra" is often heard, meaning "mate".
"lourd" (common but familiar), "lent d'esprit" (quite correct but less frequently heard)
Getting places is no idiom that I've heard of. Going places is an idiom. It means you are successful, moving up in the world.
I have never heard of frequent urination as being a side effect of an MRI. It is likely just coincidental.