Question

Read the following passage and answer the question. The International Date Line (IDL) is a generally north-south imaginary line on the surface of the Earth, passing through the middle of the Pacific Ocean, which designates the place where each calendar day begins. It is roughly along 180° longitude, opposite the Prime Meridian, but it is drawn with diversions to pass around some territories and island groups. Crossing the IDL traveling has, resulted in a day, or 24 hours, being subtracted, so that the traveler repeats the date to the west of the line. Crossing west results in a day being added, that is, the date is the eastern side date plus one calendar day. The line is necessary in order to have a fixed, albeit arbitrary, boundary on the globe where the calendar date advances.

What is the main topic of the passage?
a. International Date Line
b. International Imaginary Line
c. Time Zones of the World
d. Pacific Ocean Calendar Year

Answer 1

The passage primarily discusses the International Date Line, an imaginary line near the 180° longitude that regulates the calendar date change across the globe to maintain consistent global timekeeping.

Step-by-step explanation:

The main topic of the provided passage is the International Date Line (IDL), which is an imaginary line that serves as the demarcation point for the calendar date change. The IDL is situated near the 180° longitude, opposite the Prime Meridian, and is configured with various deviations to pass around certain territories and islands to avoid causing inconsistencies in local time and date. Crossings of the IDL result in either a day being subtracted (when traveling eastward) or a day being added (when traveling westward) to ensure consistency in the global timekeeping system.

By crossing the IDL from west to east, one actually goes back in time by losing a day, and conversely, by crossing from east to west, one gains a day. This employs a timekeeping convention that ensures more rational time and date management worldwide, despite individual time zones that change approximately every 15° of longitude traveled. A historical example that illustrates the impact of the IDL on calendar dates is the event of the bombing of Pearl Harbor, which occurred on December 7, 1941, in Hawaii (as per US calendars), but is marked as December 8, 1941, in Japan.