Question

How are time zones determined?​

Answer 1

Answer:

every 15 longitudinal degrees, the time changed by an hour, thus creating 25 time zones around the world. Over the years, government have adopted, alerted and ignored Greenwich Mean Time (GMT) as they saw fit. The US didn't sign is time zones into law until 1918.

Answer 2

Answer:

A time zone is a region of the globe that observes a uniform standard time for legal, commercial, and social purposes. Time zones tend to follow the boundaries of countries and their subdivisions because it is convenient for areas in close commercial or other communication to keep the same time.