Why is Saturday stronger than Monday?

What does below rebus means ?

By what process could you make a 'Tea-Table' into food?

What has many teeth, but cannot bite?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?

Different lights make me strange by changing me into different sizes. What am I?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

What is the end of everything?

How can a man go eight days without sleep?