Simon takes a wild guess

Here's a description of the contestant's attempt. Someone's probably working on collecting some images to illustrate it.

Simon starts out by stating that the best way to measure the weight of Mark's feet would be to submerge them in water, and measure the displaced fluid. He then seems to get caught up in how to correctly calculate the volume of an object, before giving up on the scientific method and instead taking a guess based on intuition alone. He estimates that Mark's feet weigh 0.75kg each, and that his head weighs 4.5kg, giving him a total estimate of 6kg. He earns third place in the task.

(Written by Karl Craven)