Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Client Dempsey living in one of the East Coast states of the U.S. was talking to Landon Donovan, who was living in the West Coast state of the U.S.

Dempsey: What time is it?
Donovan: Wow, It is the same time here.

How is this possible?

Remove two matchsticks to make the below equation correct.

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

You walk into a creepy house by yourself. There is no electricity, plumbing, or ventilation. Inside you notice 3 doors with numbers on them. Once you open the doors you will die a particular way. Door No.1 You’ll be eaten by a lion who is hungry. Door No.2 You’ll be stabbed to death. Door No.3 There is an electric chair waiting for you. Which door do you pick?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Eight of us go fourth, not back, to protect our king from an attack. What are we?

Can you fill the blank with the correct number?

6 30 870 756030 _____

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?