On the first day of the school a young girl was found murdered.
Police suspect four male teachers and question them.
They were asked what they were doing at 8:00 am.
- Mr. Walter: I was driving to school and I was late.
- Mr. Thomas: I was checking English exam papers.
- Mr. Benjamin: I was reading the newspaper.
- Mr. Calvin: I was with my wife in my office.
The police arrested the killer.
How did the police find the murderer?
Mr.Thomas as he cannot be checking exam papers on the first day of school.