Logic Riddles

Question: You are a surgeon who has to perform 3 operations today, but you only have 2 pairs of gloves (a and b) to perform the operations. Each of the people you are performing surgery on are infectious so you cannot touch any of them or their bodily fluids and they can't touch each other's bodily fluids. How do you perform all 3 operations with only 2 pairs of gloves?

Question: What single line can you add to the following statement to make it true?

5+5+5=550

Question: A person was born in 1940. Today is his 18th birthday.

How is that possible?

Question: A man drops an egg onto the cement. The egg doesn't break after falling 3 feet.

How could this be?

Question: A man runs into a bar and asks for a glass of water. The bartender pulls out a shotgun and yells at him. The man thanks the bartender, then walks out of the bar happily.

Why did the man thank the bartender?