Logic Riddles

Question: A man was found dead in his study. He was slumped over his desk and a gun was in his hand. There was a cassette recorder on his desk. When the police entered the room and pressed the play button on the tape recorder they heard: "I can't go on. I have nothing to live for." Then there was the sound of a gunshot. How did the detective immediately know that the man had been murdered and it wasn't a suicide?

Question: Queens can move horizontally, vertically and diagonally any number of spaces as illustrated. One piece 'attacks' another if it moves to the same tile that the other piece is on. How can you arrange eight queens on the board so they cannot attack each other?

Question: When is 1500 plus 20 and 1600 minus 40 the same thing?

Question: A bank is getting robbed and one of the robbers tells one of the tellers to give him all of the money. The teller tells him she doesn't have access to it.

Suddenly the phone rings. The robber tells the teller to answer it and not give them away. She picks up the phone and it happens to be her mother. She tells her mother "Is this an emergency mom? Call me when I get home, I could use some help painting." Then she hangs up.

The robbers continue to try to get into the vault but twenty minutes later the police show up with the tellers mom and arrest them all.

How did the police know about the robbery?

Question: A robber tried to steal the crown jewels. He got caught by the King's guards and was taken to the king. The King was feeling generous that day and asked the robber how he wanted to die. A few minutes later the king let the robber go punished yet alive.

How did the robber want to die?