What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

What happened when the wheel was invented?

100 prisoners are stuck in the prison in solitary cells. The warden of the prison got bored one day and offered them a challenge. He will put one prisoner per day, selected at random (a prisoner can be selected more than once), into a special room with a light bulb and a switch which controls the bulb. No other prisoners can see or control the light bulb. The prisoner in the special room can either turn on the bulb, turn off the bulb or do nothing. On any day, the prisoners can stop this process and say "Every prisoner has been in the special room at least once". If that happens to be true, all the prisoners will be set free. If it is false, then all the prisoners will be executed. The prisoners are given some time to discuss and figure out a solution. How do they ensure they all go free?

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

An evil man kidnapped someone and made them take one of two pills. One was harmless, but the other was poisonous. Whichever pill the victim took, the kidnapper took the other one. The victim took their pill with water and died. The kidnapper survived. How did the kidnapper get the harmless pill?

Why is the Hole below a Lock?

I make two people out of one. What am I?

What part of the chicken has the most feathers?

Our product and our sum always give the same answer. Who are we?

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