Can you fill the blank with the correct number?

6 30 870 756030 _____

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

What's the only room from which no one can enter or leave

Decode this picture on T-Shirt and tell what it says ?

If 1+9+8=1, what is 2+8+9?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

What is so fragile that saying its name breaks it?

Replace the question mark with the number below given a simple math problem.

A girl rode into a tourist spot out of the city on Thursday. She loved the place and decided to stay for a few days. She stayed for four days and then she left for back home on Thursday.

How can this be possible?

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?