More Valuable When Broken

What 5-letter word becomes shorter when you add two letters to it?

A prisoner is told he will be hanged on a morning when he will not expect it. He reasons he cannot be hanged, but he is. How?

What runs but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Four people need to cross a bridge at night. They have one torch. The bridge can only hold two people at a time. Person A takes 1 minute to cross, B takes 2 minutes, C takes 5 minutes, and D takes 10 minutes. How can they all cross in 17 minutes?

A king has 1000 wine bottles, and he discovers that one is poisoned. He has 10 prisoners to help him identify the poisoned bottle. The poison takes effect exactly 24 hours after consumption. How can he identify the poisoned bottle in just one day?

Three light switches are outside a closed door. Inside the room are three light bulbs, each controlled by one switch. You can only enter the room once. How can you determine which switch controls which bulb?