Answer:
sand is heterogeneous mixture
The definition of courtship is "the behavior of male birds and other animals aimed at attracting to a mate"
So yes, the answer is true.
A salt is an ionic compound which needs a positive charge ion and a negative ion charge to form a salt.This means that the pair of element should be a metal and non-metal.This is simply because metal atoms tend to lose negative charge electrons and form positive ions while non-metals tend to receive the electrons from the metal atom to form negative charge ions.So answer is Cl and Li.
There are two major sources of energy that power the earth's environmental systems, these are SUN AND THE EARTH'S INTERIOR HEAT.
The heat energy from the sun is the one responsible for processing all the external processes that occur in the atmosphere, hydrosphere and on the earth surface.
The energy from the earth's interior is the one that is respondsible for powering the internal processes that produce earthquakes, volcanoes eruptions and mountain formation.
