I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

Identify Me

Hint1: I am a god
Hint 2: I am a planet
Hint 3: measurer of heat

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

The Little ant seems to be always confused. Do you know why?

Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

I am a ten letters word
The first four letters have the power to rule,
Next, four-letter can be eaten.
The next three-letter represents a lady.
I can fly as well

what am I looking for?

Why do Chinese men eat more rice than Japanese men do ?

Spot what is wrong here in below Picture?

If it took eight men ten hours to build a wall, how long would it take four men to build it?