When you are at the part where you have to ride on top of a cable car over a huge crevasse so you can save a person from being a slave, it is a very good idea to hide on the back of the car (crouching), behind the last support post. When you get into the open, quickly kill the sniper behind you then continue hiding.

When you get to a bridge that hangs over the cable car, throw two sticky grenades under it on both sides of the car then quickly detonate them, This will kill the annoying enemies on it. Then, while still hiding, ready your rocket launcher by holding down the trigger until it has four shots loaded. Immediately after you pass a wall, shoot the enemies who are standing on the other side, waiting to kill you. Next, ready the rocket launcher again and shoot the small control room as soon as two more enemies walk out.