Medium logic riddles for kids with simple answers

I dig out tiny caves, and store gold and silver in them. I also build bridges of silver and make crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs my help, yet many people are afraid to let me help them. What am I?

Tom's height is six feet, he is an assistant at a butcher's shop, and wears size 12 shoes. What does he weigh?

It is greater than god, more evil than the devil, the poor have it, the rich need it, and if you eat it, you will die? What is it?

It is impossible to keep it until you give it someone else. What is that?

What is so delicate that saying its name breaks it?

I am not alive but I grow. I don't have lungs but I need air. What am I?

Give me food, and I will live. Give me water, and I will die. What am I?

Tall I am young, short I am old. While with life I glow, wind is my foe. What am I?

What has a head and a tail, but no body?

I have a bed but I do not sleep. I have a mouth but I don't eat. You hear me whisper, but I never talk. You can see me run, yet I never walk. What am I?