Answer:
I'm light as a feather yet the strongest person can't hold me for more than a few minutes. What am I?
I am a ship that can be made to ride the greatest waves. I am not built by objects, but built by minds. What am I?
I am the thing that is used to make your weight. What am I?
If you lose me, you may cause people around you to lose me too. What am I?
I can be simple or I can be complex. I can be found in this riddle or in everyday life. I can be shapes or even colors.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.