No one wants to have it, but if one got it, he does not want to lose it. What is It?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

With the help clues provided in the image, can you find the 5 digit key?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

A boy was at a carnival and went to a booth where a man said to the boy, "If I write your exact weight on this piece of paper then you have to give me $50, but if I cannot, I will pay you $50." The boy looked around and saw no scale so he agrees, thinking no matter what the carny writes he'll just say he weighs more or less. In the end the boy ended up paying the man $50. How did the man win the bet?

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

Spot 5 differences in two Christmas tree below:

Eight of us go fourth, not back, to protect our king from an attack. What are we?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?