Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?

What jumps when it walks and sits when it stands?

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?

What can you catch but never throw?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

Which of the below owl is odd one out?

Can you find out the remainder when 3^300 is divided by 5?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

They are three errirs in this question. Can you find them?