What does below rebus means ?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

Suppose you are a girl candidate and sitting in an interview. Suddenly the interviewer asks you, 'What if one morning you wake up and find out that you are pregnant?

How will you reply to such a question?

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

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

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

A man dies of old age on his 25 birthday. How is this possible?

Why did the Girl throw the butter out of the window?

To tease, King Akbar told his most clever advisor Birbal to give his daughter one thing that she can eat when hungry, drink if she feels thirsty and can burn if she feels cold. King Akbar was shocked when Birbal gave Akbar's daughter one such thing that satisfies all of the above.

What did Birbal give to Akbar's daughter?