What is the coolest letter in the alphabet?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

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?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

A man hijacks an aeroplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

I am lying and I always lie. Tell me whether I am lying or telling the truth.

In a family supper, a grandfather, a grandmother, two fathers, two mothers, four children, three grandchildren, one brother, two sisters, two sons, two daughters, one daughter-in-law, and one mother-in-law need to sit at a table.

There are only seven chairs available at the place. How many more chairs do they have to borrow so that everyone can sit down together for the suppers if everybody requires a separate chair?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?