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Figure This!

The United States covers six time zones: Eastern, Central, Mountain, Pacific, Alaska, and Hawaii-Aleutian. US territories cover four more time zones. Russia covers 11 time zones.

In order to accommodate local geography, the boundaries indicating actual time zones are not straight lines.

Some US states, such as Indiana, are in two time zones.

Two US territories, Guam and Wake Island, are on the other side of the
International Date Line
from North America.

In the US, Daylight Saving Time, which first originated during World War I, begins at 2:00 AM on the first Sunday in April and ends at 2:00 AM on the last Sunday in October.

Hawaii and Arizona do not observe Daylight Saving Time.

A 24-hour clock is used by the military and most scientists. In the 24-hour time system, the hours are numbered from 0 to 23, and there are no AM and PM designations. With this time system, 0 o’clock is possible.

A typical time zone differs from its neighboring zones by one hour, but some time zones differ by a fraction of an hour. For example, the time on the Canadian island of St. John’s differs from that in the rest of Newfoundland by 30 minutes. The time in Nepal differs from neighboring India by 15 minutes.




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