Answer:
I am round as an apple, deep as a cup. All the King's horses can't pull me up. What am I?
I'm at the head of an elephant and at the tail of a squirrel
I go inside boots and outside shoes.
I have been the beginning of ideas for all time yet I am just one simple small object the things that you can use me for can be frustrating and also I can be pretty. I have some of the most valuable thing in the world on me yet almost everyone owns me.
The more of me there is the less you see.
Two brothers we are, great burdens we bear. All day we are bitterly pressed. Yet this I will say, we are full all the day, and empty when go to rest.