A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

Move four matchsticks to the below square to form three squares?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

Next Number in the Series,

5, 16, 49, 104, ?

There is a wide field of corn. A goose finds its way into the field and starts running. Can you find out till which point the goose can run into the field?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

You can see it everyday, But cannot touch it at will. What is it?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.