Who Is the Mole?

9 contestants and 1 mole (mol). The nine contestants have to complete a series of challenges. When challenges are successfully completed, a certain amount of money is earned. When a challenge is lost, money can be lost, depending on the challenge. The tenth contestant is the mole: a saboteur. He should deliberately sabotage as many of the challenges as possible. The mole has to stay undercover as the contestants are trying to find the mole. At the end of every 2 days the contestants get 20 questions about the mole. Who ever knows least about the mole gets eliminated and goes home. At the end of the series 3 persons are left: the loser, the winner and the mole. The winner gets all the money gathered by the contestants. The mole cannot win any money.