What kind of band never plays music?

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

We have four gears with below features=> Both Gear A and D has 60 teeth=> Gear B has 40 teeth=> Gear C has 20 teeth=> Every two minutes, Gear B makes 25 full turns.What is the relative speed of Gear A and Gear B?

Can you start the fire using two pieces of wood?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

I know a nine-letter word having only one vowel.
Do you ?

In The 1st month of this year(the year 2013), I noticed that the date 13-1-13 (13 January 2013) is special.

This date is special as:

Date * Month = Year.

Can you figure out which year of this century has a maximum number of such dates?

I look at you, you look at me, I raise my right, you raise your left. What am I?

What seven-letter word has hundreds of letters in it?

Below rebus represent famous DiCaprio movie. Can you name it?