En que momento del siglo XX el crecimiento de la piblacion fue negativo

Which is a type of tectonic plate boundary?

Why are radio observatories located in valleys far away from urban centers? a. to shield them from electromagnetic interference b. to avoid sound pollution c. to avoid disturbing people living in the city d. to shield them from water vapor

Abdid is an astronomer who has been observing objects that orbit the sun in the asteroid belt. he finds a previously undiscovered round, rocky object that is not similar in shape to the rest of the asteroids. what has abdid most likely found?