I have come to realize that life is a long journey. Whether we choose to keep moving around, or we choose to stay in one place, we are on a journey. That journey is not an easy one because every day it makes our face new problems in new ways.

    When I was a little boy, I always looked forward to the next trip or the next holiday. Maybe it is because we lived in a small and boring town. When I finished school, I kept moving. In the first year out of school, I travelled with a friend and we visited over 17 countries in Europe, working in different jobs as we went. After this, I started studying. I studied at three different universities and lived in five different towns. That was my life. There was always someone else to get to know. All this carried on for many years until I got married and had my own family. When you stay in the same place, with the same persons, you start a whole new journey.

    Then you will stay in the same town, choosing one place to live and one job to remain in. There you are challenged to face life, doing things such as trying hard to get along well with your boss. You have to keep on at your job when you feel like giving it up and traveling again.

    So rather than move around on different trips, you are on a new journey. This journey of staying still is just as important as all the travels in the world.

现有一个圆心角为90°，半径为8cm的扇形纸片，用它恰好围成一个圆锥的侧面（接缝忽略不计）.该圆锥底面圆的半径为

读图1地形图，图2北美洲、南美洲图，完成下面小题。