What is ozone? a. dissolved oxygen b. the main catalyst in photosynthesis c. a type of oxygen d. a form of calcium carbonate

Which soil layers comprise the topsoil? o horizon a horizon b horizon c horizon

City in lebanon once known as the "paris of the middle east"

What change took place in china's southwest region after the communists came to power? a) encouraged by government policies, the economic base of the region changed from agriculture to nòmadic herding. b) the communist government established a special economic zone in the region. c) the leader of the religion practiced in the region went into exile, d) the leader of the religion practiced in the region was executed.