what is the date line?
It is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole.
International Date Line
The International Date Line (IDL) is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole and demarcates the change of one calendar day to the next.
where did the tropical storm zelda strike? The Marshall Islands where is this place located? It is  near the Equator in the Pacific Ocean, slightly west of the International Date Line.
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International Date Line [SEP] Introduction
The International Date Line (IDL) is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole and demarcates the change of one calendar day to the next. It passes through the middle of the Pacific Ocean, roughly following the 180° line of longitude but deviating to pass around some territories and island groups.