The empires Rome in Western Europe and Six Dynasties in Eastern Asia were connected by the Silk Road

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)

  the common sense as a pamphlet written by thomas paine. it promoted the independence of the colonies from british rule. the distribution of this pamphlet was great, it reached people everywhere and it was even read aloud at places people met. it also unite the colonists before the revolutionary war.

answer is d

incident infrared radiation is blocked. visible and ultraviolet radiation heat   earth.

earth radiates infrared radiation. infrared radiation is blocked and heats earth. visible and shortwave radiation heat earth.

earth radiates longwave radiation

longwave radiation is reflected downward longwave radiation heats earth