I shave every day, but my beard stays the same. What am I?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

Rahul decided to meet Simran so he boards a local train from Bombay station. Just after the station, there is a 1km long tunnel. The train starts and is now accelerating. Rahul is a claustrophobic guy, so what is the best position for him to sit?

Two Twins Jack and Jill were standing back to back and suddenly they started running in opposite direction for 4 kilometres and then turn to left and run for another 3 kilometres.

what is the distance between the Baggio twins when they stop ?

What has many teeth, but cannot bite?

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?

What is black when you buy it, red when you use it, and gray when you throw it away?

I never was there, I am always to be.
You have never ever seen me, not ever you will.
Yet I am the confidence of everyone.

Who Am I?