It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

A tourist visits a small town for his research. While in the town, he decides to get a haircut. Since the town is quite small, there are only two barbers in the town � one on the North Street and one on the South Street. The barbershop on the North Street is a mess and the barber has a weird and pathetic haircut. While the barbershop at the South Street is pretty tidy and the barber as well has an impressive haircut.

Which barbershop will the tourist visit for his haircut and why?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

Can you find out the number that should replace the question mark with a valid reason?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

This is a famous paradox which has caused a great deal of argument and disbelief from many who cannot accept the correct answer. Four balls are placed in a hat. One is white, one is blue and the other two are red. The bag is shaken and someone draws two balls from the hat. He looks at the two balls and announces that at least one of them is red. What are the chances that the other ball he has drawn out is also red?

What demands an answer, but asks no questions

In the Chess Board picture below white army is arranged. You need to add a black army on the board such that no piece is under any threat.
Note: Army comprised of 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns.

You can hear me, but you can't touch or see me.

What am I?