What does the below rebus riddle means?

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

Here is a conversation between a couple who both are software professionals.

Husband: Hey! What is your date of birth?
Wife Replied Angrily: It is 591062400
Husband after doing some calculations replied, "Got It".

What is the DOB of the wife?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

A new clothing store has a unique method of pricing items. A vest costs $20, a tie costs $15, a blouse costs $30, and underwear costs $45. How much would pants cost?

What goes up but never comes down?

Teacher ask the student

'Why are you standing on that chair in music class ?'.

what did student replied ?

What has lots of eyes, but can’t see?