More Valuable When Broken

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

How can you place 8 queens on a chessboard so that no queen can attack another?

Forward I am heavy, but backward I am not. What am I?

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?

I am a word that becomes shorter when you add two letters to me. What am I?

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?