You don't convert kilograms to newtons. By the time you've heard of these units, you know that 'kilogram' is a unit of mass, 'newton' is a unit of force or weight, and that mass and weight are different things.
Mass and force are <u>related</u> by Newton's second law:
Force = Mass x acceleration .
From this simple formula, you can see that in order to relate a mass to a force, you need to know an acceleration. And if the acceleration changes, then the relationship between the force and the mass also changes. So there's no direct conversion.
ON EARTH ONLY, one kilogram of mass <em>weighs</em> 9.8 newtons. The acceleration that connects them is the acceleration of gravity on Earth. In other places, with different gravitational accelerations, 1 kilogram weighs more or less newtons.
But they don't convert directly. That would be like asking "How do you convert miles to miles-per-hour ?"
Only if a force acts upon it, it can move.
I think its all four of them could be wrong but try all four !!!!!!
As they evolved and adapted, those of the fittest survived to reproduce. Those that did not adapt, died.