What is the word or phrase?

Can you make four (4) nines (9) equal 100?

If an electric train is travelling south, then which way is the smoke going?

An artist while painting a scenic beauty, decides to paint three layers of blue colour on the sky.

Which layer will go on the first?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

Below toothpicks/matchsticks indicate the group of fishes moving from west to east direction. Can you make them move from east to west by just moving three toothpicks/matchsticks?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

When can we add 2 to 11 and get 1 as the correct answer?

There are two arch enemies Messi and Ronaldo who hate each other to an extreme. One day both were going together and a Jeanie appeared in front of them. Jeanie grants 3 wishes to Ronaldo and one to Messi.

Messi replied smartly 'Give me twice whatever Ronaldo demands'.

Ronaldo asked his 1st wish 'Give me 10000 billion dollars. Soon Messi gets 2000 billion dollars.
Ronaldo asked for his 2nd wish 'Give me one mansion in every country in the world. Soon Messi gets two mansions in every country of the world?

What should be Ronaldo's third wish?