What does this rebus riddle means ?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

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 does the below rebus means?

The teacher told the student that if he told a lie then he will be expelled from school and if he told the truth then he still is expelled from school.

What can a student say to prevent his being expelled from school?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

What English word has three consecutive double letters?

Count the squares in the matchstick puzzle below?

What is the next shape from answers A, B, C, and D figure?

Today is John's birthday.
A year ago, John had five candles and he lit all the candles except the one at the last.
Now he is going to light all the candles.

How old is John Today?

(He is not five today.....)