1) capital_cities.csv:

• continent
• country
• capital_city
• capital_population

2) greenhouse_emission.csv:

• country
• total_co2
• c02_per_capita
• total_methane
• methane_per_capita

3) mega_cities.csv:

• mega_city
• country
• population

4) mountain_ranges.csv:

• mountain_range
• highest_mount
• height
• countries