What goes up but never comes down?

Buy me, smell me or deliver me, I do not change.

Who am I?

How can you drop a raw egg from a height onto a concrete floor without cracking it?

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

While going to your grandmother's house, you counted Twenty houses on the right side. While returning back to your home, you counted Twenty houses on the left side.

How many houses are there between your home and your grandmother's home?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

A Car is crossing a bridge 2 miles long. The bridge can only hold 10000 lbs, which is the exact weight of the car. The Car makes it half way across the bridge and stops. A bird lands on the car. Does the bridge collapse? Explain.

Solve below rebus puzzle?

If 2 workers can complete painting 2 walls in exactly 2 hours.

How many workers would be needed to paint 18 walls in 6 hours?