Final answer:
In "The Sniper," the IRA sniper tricks the enemy by making it seem like he has been shot using his cap and rifle as a decoy, which eventually allows him to shoot the opposing sniper.
Step-by-step explanation:
In the story "The Sniper", the IRA sniper employs a clever ruse to trick the enemy. He tricks the opposing sniper into thinking he has been killed. To do this, he places his cap on the barrel of his rifle and carefully raises it over the parapet of the roof where he is hiding. The enemy sniper shoots the cap, and the IRA sniper lets his rifle drop and slumps over the roof as if he has been hit. Convinced he has killed the IRA sniper, the enemy sniper becomes careless, giving the protagonist a chance to shoot him with a revolver.