Answer:
What is at the end of a rainbow?
This patch of land stands alone
What is not a ball but yet a sphere, and holds all lands and people year after year?
What falls down but is never injured?
Watches students at the prom to make sure there's no funny business.
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.