why number 8549176320 is one of a kind?

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?

An inspection by the superintendent of St. Joseph School was scheduled on the next day. The class teacher Jenifer knew that he would be asking questions from her class and she would have to choose a pupil to answer. To offer a perfect impression over him, the teacher explained certain instructions to the students to maximise the chances of getting correct answer every time.

What did she say to the students?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

When we see 2 but call 10?

What runs around the whole yard without moving?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

What word is identified by the below rebus?

Your Your Your Your Your
Your Your Your Your Your

Can you find a number that lies one third of the distance between 1/3 and 2/3?

what does the below rebus means?