One night, a woman receives a call from the police.
They tell her that her husband was murdered, and she should come to the crime scene as soon as possible.
The woman drops the phone, shocked, and drives 20 minutes to the crime scene.
As soon as she reaches the crime scene, the police arrest her and she is convicted of murder.
How do the police know she committed the crime?
The farmer takes seven trips over—here are his steps:Take the goat over
Return
Take the wolf or cabbage over
Return with the goat
Take the cabbage or wolf over
Return
Take goat over