What always comes into a house through the keyhole?

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?

I’m tall when I’m young, and I’m short when I’m old. What am I?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

Can you fill the blank with the correct number?

6 30 870 756030 _____

Accidentally, two trains are running in the opposite direction and enter a tunnel that is 200 miles long. A supersonic bird that has fled the lab and taken shelter in the tunnel starts flying from one train towards the other at a speed of 1000 mph. As soon as it reaches the second train, he starts flying back to avoid collision and meets the first train again at the other end. The bird keeps flying to and fro till the trains collide with each other.

What is the total distance that the supersonic bird has traveled till the trains collided?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

During a secret mission, an agent gave the following code to the higher authorities
AIM DUE OAT TIE MOD

However, the information is in one word only and the rest are fake. To assist the authorities in understanding better, he also sent them a clue, If I tell you any one character of the code, you can easily find out the number of vowels in the codeword.

Can you find out the code word?

Count the number of squares in the picture below.

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?