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

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

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

How can you leave a room with two legs and return with six legs?

There are 2 cops parked along a one-way street looking for traffic violations. They spot a taxi driver going in the wrong direction, yet they do nothing.

Why?

It belongs to you, but other people use it more than you do. What is it?