What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
? ? ? ?

What does the below mathematical rebus mean?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

What's a single-digit number with no value?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

Different lights make me strange by changing me into different sizes. What am I?

I am a five-letter word and comprises two different vowels and three same consonants. I am so strong that I can spoil your entire work.

Can you find out who am I?

That attorney is my brother, testified the accountant.

But the attorney testified he didn't have a brother.

Who is lying?

Before reading ahead, you must know the fact that only one of the people here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?