Relative humididty is the amount of water vapour present in the air expressed as a percentage of the amount needed for saturation at the same temperature.
b:inland/interior regions
Two major problems associated with petroleum products are the environmental hazards associated with its extraction from the earth and also the environmental impact of its burning which emits greenhouse gases into the atmosphere which has been shown to cause global warming and climate change.
Henry Ford's famous automobile that was the starting point for affordable mass-production in automobile manufacture was the Model T.
Hope that helped! =)