Sand is made of tiny pieces of rock that have been worn down by wind and water. Explain why the formation of
sand is a physical change.

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.

What is special about a dc circuit ?

Which branches of natural science include the study of an organism that lived 10 million years ago