How might a system be described in terms of matter and energy?

All of the following came out of china and were exchanged along the silk road, except a. papermaking b. block printing c. buddhism d. compasses select the best answer from the choices provided a b c d

Plz answer ! find the alps. what countries and country borders intersect this major mountain range? which borders seem to be defined by the edges of the mountains? which borders seem to be defined by the edges of the mountains? which borders cut across the mountains?

Name two factors that, "power of magnetic field " of earth.