North America metropolitan area by population in North America: Greater Mexico City. Canada also breaks into the top ten largest metropolitan areas with the Toronto metropolitan area having six million people. The proximity of cities to each other on the Canada–United States border and Mexico–United States border has led to the rise of international metropolitan areas. These urban agglomerations are observed at their largest and most productive in Detroit–Windsor and San Diego–Tijuana and experience large commercial, economic, and cultural activity. The metropolitan areas are responsible for millions of dollars of trade dependent on international freight. In Detroit-Windsor the Border Transportation Partnership study
Electrical wiring in North America condition of use (suitable for dry and damp locations) for electrical wire and cable. Wire with THWN or THHN insulation is commonly used in the AC electrical distribution systems throughout North America, usually at voltage levels from 110 to 600 volts. This type of insulation is used for both copper and aluminum conductors which are either solid or stranded, depending on size. Many wires are rated both THWN and THHN, and are suitable for use in dry locations up to 90°C (194°F), or wet locations up to 75°C (167°F). Electrical wiring in North America Electrical wiring in North America follows