It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South. Suddenly one of them said to the other, "Why are you smiling?"

How did he know his companion was smiling?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

Akbar summoned Birbal out of anger.
He told him that he will have to face death.
He asked him to make a statement and if the statement is true he will be buried alive and if the statement is false, he will be thrown at lions.
After hearing Birbal’s statement, Akbar could do nothing but smile.
He gave him 5 gold bars and let him go.

What did Birbal say?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Can you find the mistake in the below statement?

Rearrange the letters in "new door" to make one word.

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

What is the coolest letter in the alphabet?

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?