What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

I am quite hot but become too cold if you remove the first two letters. What am I?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

What does this simple rebus mean?

What begins with T, ends with T, and has T in it?

Jack and Joseph are well-known golf rivals. One Day during a match, they were level at a score of 30. Jack hit a bad shot and Joseph added 10 to his score. Joseph then hit an awesome shot and he won the game.

How ?

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

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

You know three triplets: Frank John and Wayne (need to return your money). Frank always tells the truth while John and Wayne always lie. You meet one of them on the road and can ask him a three-word question.
Which question, will you ask?