What is harder to catch the faster you run?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

You are given 2 eggs.
You have access to a 100-storey building.
Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor, Both eggs are identical.
You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.
Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

The captain of a ship was telling this interesting story: "We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly." How can that be possible?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

Do You See It?

Which is faster, Heat or Cold ? Explain.

Which part of London exists in France as well ?

A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks - so that each deck contains an equal number of face-up cards. Remember, you are blindfolded.

How will you do it?