Your first trip to Mount Everest. Which way should you go? Use your compass to find your way. A compass always points North, so for each problem, begin by rotating your compass until the red arrow is lined up with the red N.
http://www.pbs.org/wgbh/nova/everest/earth/lostshock.html
Niciun comentariu:
Trimiteți un comentariu
Rețineți: Numai membrii acestui blog pot posta comentarii.