题目内容：

Strange things happen to time when you travel because the earth is divided into twenty-four zones (时区), one hour apart (一个时区相差一小时). You can have days with more or fewer than twenty-four hours, and weeks with more or fewer than seven days.

If you make a five-day trip across the Atlantic Ocean (大西洋), your ship enters a different time zone every day. As you enter each zone, the time changes one hour. Traveling west, you set your clock back, traveling east you set it ahead. Each day of your trip has either twenty-five or twenty-three hours.

If you travel by ship across the Pacific (太平洋), you cross the international date line (国际日期变更线). By agreement, this is the point where a new day begins. When you cross the line, you change your calendar one full day, backward or forward. Traveling east, today becomes yesterday, traveling west, it is tomorrow.

1.Strange things happen to time when you travel because ______.

A. no day really has twenty-four hours    B. no one knows where time zones begin

C. the earth is divided into time zones    D. how time flies

2.The difference in time between zones is ______.

A. one hour    B. more than seven days

C. seven days    D. one day

3.If you travel across the Atlantic Ocean, going east, you set your clock ______.

A. one hour ahead in each time zone    B. one hour ahead for the whole trip

C. one full day back for each time zone    D. neither back nor ahead

4.From this passage, it seems true that the Atlantic ______.

A. is in one time zone    B. is divided into twenty-four zones

C. is divided into five time zones    D. is divided into seven time zones

5.The international date line is the name for ______.

A. the beginning of any new time zone

B. any point where time changes by one hour

C. the point where a new day begins

D. the point between two different zones