Factual error: If the two snipers were placed in the same building right on top of each other, and as far away from the target as we see, the difference in the angle of the two bullet trajectories would be very small. The difference shown by the plastic sticks would at that long distance mean a huge difference in height.
Add timeJacob La Cour
Continuity mistake: In the beginning of the movie, a man gets out of a car and walks toward a street while talking on a phone; he then starts to grab his upper left arm while vomiting. Before he falls to the ground, notice that there is a very noticeable amount of vomit on his chin. In the next shot his chin is almost spotless.