The saying "What goes up must come down" is an appropriate starting point. If you fire a gun into the air, the bullet will travel up to a mile high (depending on the angle of the shot and the power of the gun). Once it reaches its apogee, the bullet will fall. Air resistance limits its speed, but bullets are designed to be fairly aerodynamic, so the speed is still quite lethal if the bullet happens to hit someone. In rural areas, the chance of hitting someone is remote because the number of people is low. In crowded cities, however, the probability rises dramatically, and people get killed quite often by stray bullets. Most major cities have laws in place to try to keep people from shooting guns into the air in celebration.
People have been fighting with one another longer than humans have recorded their history. Conflicts are unavoidable. But can anyone say for sure when the first war broke out? Why did we invent wars, anyway?
Picture yourself deep behind enemy lines, taking calculated risks to gather information about the enemy. This is Army reconnaissance work. How can you earn yourself a spot among the reconnaissance ranks?