Forward I am heavy, but backward I am not. What am I?

I fly at night, I hang upside down, and I am not a bird. What am I?

I'm tall when I'm young and short when I'm old. What am I?

What building has the most stories?

What begins with T, ends with T and has T in it?

I have cities but no houses, forests but no trees, and water but no fish. What am I?

What has lots of eyes but can't see?