Answer to #71: Biggs, who saw the smoke, would be first; Carpenter, who saw the bullet strike the water, would be second; and Anderson, who heard the report, would be last of all.

A man was killed in his office. At the time of murder there were only four people in the office: Bill, Tom, Harry and Mike.

When police interrogated them, they gave the following statements.

Bill: "Tom did it."
Tom: "Bill did it."
Harry: "Tom's telling the truth."
Mike: "Harry's not lying."

After analysis, the police found out that only one person was telling the truth and the rest were lying. Can you analyse the statements and determine the killer? [Slide for answer]