Answer:
C.They are made mostly of limestone.
Explanation:
Valley regions are mostly made up of limestone. the valleys of Ridge and Valley region are made up of sedimentary rock such as Limestone, dolomite, and shale. These limestone are extracted from these valley and use in the production of gypsum and other industrial products. Valleys are present at various height above sea level.
Answer:
new benefits and new dangers
Explanation:
Living on reclaimed land in Mexico City has provided new benefits and new dangers.