This is similar to China, which has 5 timezones wide and they have one standard national timezone. The US is far wider when you consider Alaska, Hawaii and the

This is similar to China, which has 5 timezones wide and they have one standard national timezone. The US is far wider when you consider Alaska, Hawaii and the island territories in the Caribbean and the Pacific. It spans from UTC+10 (Guam) to UTC-10 (Hawaii / Aleutians).