I? Clever?

I think that many Khabrovites have nowhere to apply their intellectual abilities.
Therefore, I suggest users to play the next game. I come up with a problem from the field of natural sciences, for the solution of which it is unlikely to need knowledge wider than school knowledge, but it will require the ability to think logically.

It seems to me that it should be more interesting than the sports ChGK.

If people need it, I can start right now.